# Is Algae worse with LED lighting?



## Barbara Turner

I was chatting to the owner of my local fish shop about planted tanks and Algae and he said that
"Now we sell LED lighting we have far more customers having problems with Algae"

My first question is
Do we think that this is correct?
I’m sure we still had algae problems but are they fewer?

My initial thought was that this is just due to the fact that most LED units are far more powerful than the fluorescent units he previously sold but looking around most of the LED lights for sale are less than 30w so I’m not convinced this is true.

Looking at the light spectrum of a fluorescent bulb, it produced far more UV light than LED’s do, (even if that wasn’t much). I also understand that UV is also harmful to plants but even more so to Algae.

Reading up on recent research plants can often adapt to UV lights and survive, it just made me wonder if we should add very low levels of UV light to our fish tanks.


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## Tim Harrison

Could be possible, although I'm not sure about the photo response of algae vs higher plants, and I happen to be one of the minority that believes spectrum matters.
However, I think that it perhaps has more to do with your initial thought. Every LED light is different, whereas the output of fluorescent tubes is fairly consistant.
With LEDs there isn't really any rule that can be applied across the board and it's this lack of consistency that could easily lead to algal issues.

I've used a few different types of LED unit and know from personal experience how difficult it can be to get the intensity right, especially if you are unfamiliar with the unit.
My Radion XR15 FW, has a UV LED in the array, a legacy from the manufacturers reef origins, and regardless, if the intensity is too high algae starts creeping in from the edges.
That's is why I always recommend buying a LED light with a dimmer or a light that can at least be retrofitted with one.

In addition, at the end of the day there is still no substitute for good tank husbandry, and effective implementation of CO2 through good flow and distribution. As well as a good fertz regime of course. It's these things that folk often get wrong.
And, I'm sure that your LFS owner is very knowledgable, but IME these guys are more likely to lead hobbyists astray.


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## BubblingUnder

Tim Harrison said:


> the output of fluorescent tubes is fairly consistent.


Not sure this is true over time. I used to run 2 fluorescent tubes on my aquarium & had to swap them over carefully to maintain roughly the same light levels. If I didn't I noticed more algae appeared as the amount of available light fluctuated. Perhaps LED's suffer much less degradation over time.

This article describes the light reduction on T8 fluorescent tubes over time but I can't vouch for the science.
https://www.lrc.rpi.edu/programs/NLPIP/lightingAnswers/t8/06-t8-lumen-maintenance.asp


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## zozo

Since i'm back into the hobby a few years now with multiple tank syndrom. I've builded several diy led fixtures with different types of leds, SMD, COB type leds.

I absolutely can't say anything about spectrum, since most scientists in the field are yet not sure if and how the plant uses the complete spectral range of light available. So it could very well be that plant sp. independendly biologicaly developed to use available light differently and maybe have a preference. Take for example a fern that prefers to grow in shaded spots. It evolved to grow in the shades and we know shaded light has more Blue wavelenght in its spectrum. Even if we don't know i can imagine a fern might be happier with less intensity and more blue, compaired to its flowering sun loving counterpart that is happier with a lot more intensity and a tad more red.  If that is so, than algae probably has simmular prefernces.. It might be true for any photosythesizing organism, biologists have found evidence of photosythesizing bacteria in nature prefering the red spectrum.

https://www.futurity.org/far-red-light-bacteria-751962/

If algae growth is worse with led lighting in general imho more likely more comes down to the big difference between the way led light is distributed compaired to a tube light.

A led is simply much more intense in usefull light than a tube because it directs all light straight down in a rather narrow angle between 60° and 120° depending on the type of led. A tubelight scatters the light in a 360° and a big part needs to be reflected down again. Not only loosing intensity but the reflector likely also changes the spectrum. Anyway, a led gives a lot more usefull bundled light without much spectral loss and if you want to spread it you need multiple sources in aray. Than even if our eyes do not percieve it as more intense, because if you look straight into it you are blinded to much by both telling you zip, than all you have is look at the invironment and also not realy see the difference in intensity. But a 1000 lumen led aray produces at least 50% more usefull light with greater intensity than a 1000 lumen tubelight.

Than a dimmer indeed aint redundand luxery.. More likely a must have..


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## Tim Harrison

Tim Harrison said:


> the output of fluorescent tubes is fairly consistant.





BubblingUnder said:


> Not sure this is true over time.


Okay, maybe I should have qualified that, by writing...relatively consistant by comparison...


BubblingUnder said:


> This article describes the light reduction on T8 fluorescent tubes over time but I can't vouch for the science.


We've had a few discussions on this topic over the years and I think the consensus was that it's largely mumbo jumbo concocted by manufacturers to get us to buy more tubes, for instance https://www.ukaps.org/forum/threads/when-to-change-bulbs.34744/#post-371449


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## mort

I think a lot of this has nothing to do with led but more to do with the modern world. I ran a lfs and lots of people who kept plants had no real problems with algae until you actually saw a picture of their tank. Bba was nearly always constant and I think they just thought it was a normal part of the tank. It's only today with the way infomation is easily available that people actually know different. 
So for me the rise of led has coincided with the rise in forums and showing off what we have. 

But just to contradict myself a little there has been a link with certain led colours promoting algae in marine tank, especially green and red. I'm not convinced these are any worse than a full spectrum light source but it's easy to just turn them down which is actually a benefit.


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## Simon Cole

I am not sure that LED's do not suffer from considerable "spectral loss". The website below states: "LEDs emit light in a very small band of wavelengths, emitting light of a colour characteristic of the energy band gap of the semiconductor material used to make the LED". Source: http://www.lllwww.co.uk/about_led.html. 
When I researched my LED chips, I found that the waveband was incredibly narrow. I would need specialist scientific equipment to actually measure an LED array, but overall the results are unlikely to be much different from that hypothetical argument. When we consider that fluorescent tubes have multiple excited electron states - they have considerably more distributed wavelength banding. Now the interesting part comes when we consider the wavelengths preferred by algae as opposed to plants, and their ability to utilise that energy. I would say Barbara, that like Tim, I also happen to be one of the minority that believes spectrum matters. That is to say, I would prefer any technology that gives me a broader band of wavelengths that is engineered towards plant growth and not algae. 
I am not sure that semiconductor technology is sufficiently advanced enough to give similar flexibility in design-engineering choice.  
I have not reviewed all the scientific literature, but if somebody knows more that would be really interesting.


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## zozo

@Simon Cole 

http://scapefu.com/lighting-planted-aquarium-cara-wade/

https://www.facebook.com/cara.wade.9


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## dw1305

Hi all, 





Simon Cole said:


> Now the interesting part comes when we consider the wavelengths preferred by algae as opposed to plants


The marine red algae (<"Rhodophyta">) are often found towards the lower end of the photic zone, where the only wavelengths of light that haven't been scattered are the at the blue end of the spectrum. They have different photosynthetic pigments, including phycoerythrin.

But there isn't really a difference for the "green algae" (<"Chlorophyta">), they share the same photosystems (chlorophylls a & b etc.) as all the vascular plants (mosses, ferns & flowering plants), because they have a common ancestor (they all belong to the clade <"Chlorobionta"> or <"Viridiplantae">).



 

cheers Darrel


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## Tim Harrison

At first it appears that LED lighting can be a bit of a minefield. But I reckon it's fairly straight forward really. Choose a light that you like the colour rendition off; the visual spectrum is the same as the photosynthetically active spectrum give or take a few nm (400-700nm) so it's a good bet it'll be perfectly adequate for growing plants. Make sure it's dimmable and has the intensity to grow the plants you want and away you go. 

As for LEDs having a narrow band of wavelengths; both the visual and photosynthetically active spectrum are narrow, and only a very small part of the electromagnetic spectrum . And further, many of the new generation of LEDs units are RGB which I think gives better colour rendition and perhaps helps to bring out the reds in some plants and maybe also helps to encourage the compact growth forms that aquascapers find attractive; photomorphogenesis

As for the OP... is the quality of LED light more likely to encourage algae than say T5s? Darrel's post above would suggest not. Either way it shouldn't really make that much difference in a well maintained and balanced aquarium.


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## zozo

What i understood from the theory how White light is created with LED is.. All crud leds are in fact only emitting light in the blue spectrum.. Than they need to be coated with Phosphor to emit white light.


 



Since it a natural sourced product there is a huge difference in the used phosphor contents, pure phosphor is white, but containing contaminents it can have a range of colors yellow, green and red, in different color intensities one can look orange and the other red and both are still phosphor. Thus it kinda depends on the manufacturers phosphor source what kind of white their led emits. The phospor filters parts of the blue into a mixture of RGB.

https://en.wikipedia.org/wiki/Phosphorus

As i experienced myself, buying leds with a 10000K (cool white) specefication and looking at it it was more emitting pink light than blue. And a 10000K from another manufacturer looked completely different again without any vissible reds at all. I guess the manufacturer needs to make consesions regarding the purity of their phospor to create a light in the so called K standard we use in the trade.

Than it seems, depending on techniques used applying this coating it can result in sone spectrum differences.


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## Tim Harrison

I suppose that could really answer the OP, in that LEDs from different manufacturers are not all the same. If you follow the logic, it's unlikely to be LEDs that cause algae since surely they are all too different to have that one thing in common...a quality or spectrum of light that causes algae ?


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## zozo

Tim Harrison said:


> I suppose that could really answer the OP, in that LEDs from different manufacturers are not all the same. If you follow the logic, it's unlikely to be LEDs that cause algae since surely they are all too different to have that one thing in common...a quality or spectrum of light that causes algae ?



That's indeed also the logic i followed.. As said builded several led fixtures over the years and the specs given by the wholesalers are 2700K, 6500K and 10000K, very few times encountered 8000K. But in general the first 3 are most common. Or they give no K at all and say Warm, natural or cool white. Than if you compare them and clearly see one different in color than the other but have been given the same specs. Than it's obvious that or they do not measure it or each development lab has it's own color chart to determine it. I wouldn't know, how or what. It kind a seems a giving a K number gives a more professional appearance to the customer, rather than only Warm. Than it's choosen by the seller to target a certain customer.

But in the end you do not know what you realy get. I doubt there is anybody who knows what 6500K realy stands for and how it should look. How do you actualy determine a light color?

Than if you combine the 3 given K colors you mix it completely up and gives the ability to slightly change it to own preference.

Not to forget and seldomly given in the specs, some leds change slightly in color output when dimmed (receiving less voltage) or when getting warmer. Than take for example invironmental temperatures fluctuate according to the seasons with rather dynamic cooling propperties for the leds. With an average 20° winter and up to 35° summer temps. Can give you a dynamic spectrum all through the year.. 

There is just to much we do not know and maybe don't notice with the nacked eye.

I also do not know, than i have to guess and i think the LED relatively gives more PPFD per sqaure than any other light with the same output specs. Because it's much narrower beam angle.  And that imho is more likely the reason why many people experience an algae outbreak after switching to led..


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## Tim Harrison

zozo said:


> I also do not know, than i have to guess and i think the LED relatively gives more PPFD per sqaure than any other light with the same output specs. Because it's much narrower beam angle. And that imho is more likely the reason why many people experience an algae outbreak after switching to led..


That's what I think too


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## Simon Cole

Thanks for the info Darrel. I would feel a lot more confident choosing an LED array after reading these posts, so it is really helpful stuff. 
There are a few manufacturers that include lenses over the LEDs to widen the beam angle.


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## zozo

Simon Cole said:


> There are a few manufacturers that include lenses over the LEDs to widen the beam angle.



That's because not all lenses are suitable, a lot give a prims effect bellow the water level inside or outside the aqaurium.




Few years back searching info for my first led buildibg experiments i stumbled uppon a forum thread with pictures of someone who made use of lenses. Creating several rainbow colored beams in the water. After removing the lenses it was normal again. Can't seem to find that thread back, i have forgoten the proper search query i guess.


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## Simon Cole

Cheers Marcel, I didn't know that.


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## Tim Harrison

The Radion I mentioned previously has a lens over it. There is/was a choice between 80° and 120° spread, it comes with the latter as standard now. However, the lens still doesn't prevent hot spots; higher light areas where algae is likely to appear.
It also creates a split spectrum, or rainbow effect, which I actually quite like tho'; that and glitter lines, which are spectacular.

Mr. Teapot's Green Pekoe Pond showing the rainbow effect created by the Radion XR15 FW lens https://www.ukaps.org/forum/threads/green-pekoe-pond-40-litres.27575/page-14#post-390344...




Another of Mr. Teapots images from the same journal showing the Radions LED puck, with lens...


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## dw1305

Hi all,





Tim Harrison said:


> is the quality of LED light more likely to encourage algae than say T5s? Darrel's post above would suggest not.


That would be my guess. It can't really make any difference for the green algae, and all the other photosynthetic organisms have evolved to use sunlight, and photosynthesis has probably <"only evolved once"> (but at least <"3,500,000,000 years ago">). 

Because of the different photosynthetic pigments in diatoms (chlorophyll c, fucoxanthin), cyanobacteria (phycocyanins, phycoerythrins) and red algae (phycoerythrins) they might use slightly different wavelengths of light, but you are still back to having all evolved in sunlight, the spectra of which is pretty constant.

If you found a planet, with photosynthetic organisms, that orbited a star that emitted light at different wavelengths I would bet (a pretty safe bet)  that the pigments would differ, but would have evolved to maximise energy interception at the appropriate wavelengths. We think of visible light as different from all the other electromagnetic wavelengths (390 to 700 nm), but it isn't, we've just evolved to "see" it. 

If I was to guess that any of these groups are preferentially favoured by different wavelengths of light, when compared to the Viridiplantae, my suggestion would be the Red Algae (including BBA and Staghorn). If you find sub-tidal red algae in deep rock pools on the shore they are often "bleached", presumably by the extra energy of the sunlight when it isn't attenuated by a reasonable depth of water.

Because the freshwater "pest" red algae (_Compsopogon & Audouinella spp.) _aren't red that makes me think that they have a lot of  carotenoid pigments, that mask the photosynthetic pigments and give them some form of  "sun-cream".

cheers Darrel


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## Oldguy

I am of the view that spectrum matters, though plants do grow under less than ideal conditions.

When using fluorescent tubes I used cold white and glowlux. It gave decent colour rendering & plant growth.

When I moved over to LED's (the luminair required re-tubing and one of the ballasts was starting to corrode and most importantly for me was the price of LEDs were falling) I chose units with multiple colours as well as 'white'. In addition I added other LEDs with a cone shaped output as spotlights. These are easy to change and are currently a mix of white and red/blue hydroponic lights. None can be dimmed (to my knowledge) but each bank are on timers. There can be a spectral shift as voltage is lowered on LEDs but whether it is significant is doubtful.

I view some algae in a tank as natural (try keeping the spores out, they are in the air we breath) but try and run conditions that favour vascular plants

Views from lfs, ask the the same question in ten different shops and you will get at least twelve different answers.

Light intensity, CO2 and fertzs and striking a balance is key.


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## Barbara Turner

Having spent a little time reading arround the subject, I came to the conclusion that plants can use a whole range of frequencies just with different efficiency. Sadly I haven't read anything that suggests algae is any different.




 


(research by migro on non aquatic plants)

Ppfd values are king the more light you have the faster plants and algae will grow.

I'm surprised that most the lights don't match the spectrum of the sun.The sun's has about 25% blue and a balance if green and red. That is about 5k colour temp.
I don't understand why we normally go for 6500k.

I think that colour spectrum does make a difference in plant shape but most of the commercial led lights available have a lot more blue light that will shorten stem length. ( not a bad thing) but I doubt there is enough of a difference between manufacturers to make any noticeable difference. The output power makes a far bigger difference

What is important is how the tank looks. Know one what's a pink full spectrum tank even if it gives great growth and saves them 10% on there electricity usage.

I would love to do some testing to see how low levels of uv light affect various algaes and plants. I'd need two identical tiny tanks and run one with a bank of uv leds. Then ask people to send me there algae covered plants.
Ideally set up a camera on time lapse. See if there is a level that kills the algae and not the plants.

Getting co2 and flow arround the tank also make a big difference. But it might be a useful weapon against algae.


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## zozo

I started building led fixtures about 5 years ago, at that time about every serious LFS and every serious hobbyist was still in a lot of doubt that led lighting was usefull for growing plants. I still remember an article on the Green Machine website explaining why they didn't sell LED fixtures in their shop. It still was believed no good for growing plants. Anyway it took less than a year for this article to be removed and changed into "Now we do sell led lights!".

This was all due to the rapid evolvement in the led industry.. Also due to that manufacturers that essamble led lights actualy always run several steps behind. They have to come up with a design based on the current available technique and than to make a profitable commercial product need to produce a certain amount of stock that can not be upgraded on the fly. You have to make a 1000 and have to sell a 1000.

Since i'm a vivit DIY'r i noticed all off the shelf available lights in the LFS were way behind, producing a stock that needs months maybe up to years to be sold. And this while the led industry evolved with better performong techniques in few months time, new types of leds doubling in performace roled of the line every 2 months., improving performance. durability and color rendition.

In the begining i builded 3 different led setups in a year time with always with the latest new designs i tracked down. SMD strips ranging from the first best available i used with 25 lumen per led to 3 months later 65 lumen per led. And that very same year the COB led was introduced 12 volt - 15 watt with 110 lumen per watt  over a surface of 90x40mm.. That soon after that became smaller and more powerfull.

3 times a different build in a year and each time more than doubling performances..  Mean while the LFS was still selling the same old unsufficient cr#p. Even today i still see Light Tube LED replacements that hurt my eyes when i look inside and see which leds are in it and not from brightness. It simply is new old stock not worth buying..

That is something for the LFS to think about before they give an opinion on LED in general. Already before their product is sufficiently reviewed and tested to come up with an opinion, better and completely different ones already available. Thus by the time you have developed an opinion say it takesyou 6 months, it's already outdated and simply only applicable to that particular build and not for led light in general.

Look it up for fun how many different types of leds have been developed in the last 5 years.. You will not see the forest for the trees. And it still s running a rather fast pace..


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## Barbara Turner

zozo said:


> 3 times a different build in a year and each time more than doubling performances..  Mean while the LFS was still selling the same old unsufficient cr#p.




I'd never really thought about how fast LEDs are improving.  As they get more efficient they generate less heat and the whole units get smaller and heat management gets easier. 
The thing that is really shocking is the crazy prices they are charging for low powered tubes.


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## Tim Harrison

I don't think UV will make any conceivable difference, like I mentioned in post #2, at least those levels of UV low enough not to damage plant cells beyond their natural "sun screen" mechanisms. And I agree, just pick a light you like the colour rendition of, chances are it'll be good for growing plants since the photosynthetically active spectrum and the visual spectrum are pretty much one and the same, see message #10.


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## tiger15

Dennis Wong has an in depth discussion on plants and light spectrum.  Accordingly,  plants can utilize all light spectrum, including green light previously dismissed.  

https://www.advancedplantedtank.com/rethinking-light-wavelength.html

Algae, being more opportunistic, care even less about light spectrum, besides, there are so many species of algae out there that it’s not possible to paint a broad brush to all.

So I don’t think spectrum of UV light will promote more algae than fluorescent.  On the other hand, the directional nature of led may reduce algae on the tank walls by limiting light falling on the walls.

The exception is energetic UV light which may harm certain algae due to delicate cell walls.  I notice my outdoor tubs are never bothered by bba, though green water and other filamentous algae can take over.


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## Tim Harrison

Algae are plants as well, and will often grow in the same conditions that favour higher plants, so perhaps not so opportunistic after all. Here's what our AWOL resident expert Clive @ceg4048 has to say on the matter https://www.ukaps.org/forum/threads/direct-sunlight-causing-algae.14980/#post-157897


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## dw1305

Hi all, 





dw1305 said:


> If I was to guess that any of these groups are preferentially favoured by different wavelengths of light, when compared to the Viridiplantae, my suggestion would be the Red Algae (including BBA and Staghorn).


I've just found the link to a paper that @AndyMcD sent me a couple of years ago, <"Effects of temperature, irradiance and photoperiod on growth and pigment content in some freshwater red algae in culture">, that is relevant to this thread. From the abstract





> Most freshwater red algae had the best growth under low irradiance ((65 μmol photons m–2 s–1), confirming the preference of freshwater red algae for low light regimens. In general there was highest growth rate in long days and low irradiance........


_Compsopogon coeruleus _is "Staghorn" and one of the _Audouinella_ spp. is likely to be BBA.

There are a few other papers that have cited this one that might be useful, this is a Brazilian one <"Photoacclimation in three species of freshwater red algae">. 

The papers all seem to suggest that High PAR and a short photo-period are the least favoured condition for Red Algae growth, although they seen <"quite plastic in their response to light">.

Somewhere I have some correspondence which says that BBA like red algae are common in the Igarapes of the Peruvian Amazon, but so far I haven't found it (I thought it was in a thread on UKAPS).

cheers Darrel


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## zozo

> Most freshwater red algae had the best growth under low irradiance ((65 μmol photons m–2 s–1), confirming the preference of freshwater red algae for low light regimens. In general there was highest growth rate in long days and low irradiance........



It fits this current situation 100%..


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## tiger15

I can attest that my outdoor tubs and planted bowls  by the window that receive direct sunlight don't get BBA.  My very low light fish only tanks, less than 30 PAR, also don't get BBA.  It is my medium light planted tank,  around 60 PAR, that gets BBA.  So direct sunlight is unfriendly to BBA, but unsure if it is the high intensity or the UV component that inhibits BBA.  I don't think artificial high light can compare with direct sunlight (300 to 1000 PAR ) in intensity, and the absence of UV,  to have an impact on BBA.


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## Tim Harrison

It could also be that the environmental conditions aren't necessarily more suitable for BBA, but that they are perhaps less favourable for other species, which means that BBA can compete on a more level playing field.

When I was researching the impact of groundwater drawdown on wetlands I sometimes found plant species that usually prefer much drier conditions growing in wetland fringes; even a slight change in environmental conditions can be enough to change the dynamics of an ecosystem, particularly a fragile one susceptible to tipping points.

I'm digressing slightly but, it's likely that these species have always grown in less favourable conditions but largely unnoticed or passed off as outliers. I think wetlands or other habitats at the extreme range of tolerance, like old toxic mine workings, are among the few places some species can be found now since their preferred habitat has disappeared, usually under concrete or a sea of wheat, or it's been laid to grazing and they've become outcompeted by C strategists like perennial ryegrass.


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## Barbara Turner

I still think the affect of adding UV lights to an algae covered aquarium tank could be very interesting.  We know its very popular in indoor growing. Look at the spectrum of this bulb. 
( I'm not suggesting this much, or using this bulb ) 



 
Recent research has helped the benefits of UV in horticulture come to light.
UV light activates a plant’s natural defense mechanisms, producing a sort of “sun screen” to protect itself from the damaging light. Some plants can produce as much as 15 different defense proteins with exposure to UV. As the amount of UV increases, so does the production of defense proteins.
We know that Algae is a far a simpler single cell species.. I doubt all algae has the ability to protect itself from UV. I doubt it is a magic bullet that will kill all algae, but by the sounds of it might give BBA a hard time. 

It also might not be a bad thing for any fish, UV light exposure stimulates the pigment to reproduce faster, increasing the fish’s natural tolerance levels of UV light. The amount of UV light a goldfish receives has an influence on its color too. Fish exposed to lower levels of UV tend to be paler, while those exposed to higher levels have more vivid colors.


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## zozo

Barbara Turner said:


> The amount of UV light a goldfish receives has an influence on its color too. Fish exposed to lower levels of UV tend to be paler, while those exposed to higher levels have more vivid colors.



I keep goldfish and they produced quite a lot of fry over the years.. All are actualy born black..  And i red this statement before but i do not realy see it back in mine. The oldest i have i bought completely orange, but she got completely white in a few years time. Even tho she gets loads of sun...

Here she is.. 




And all her offspring is born outdoors recieving all the sun they can get for the majority of the day. Still About 4 of here babies are equaly white all over same as their mother. Actualy not only white but also body shape and relative tail size is simmular..

I wondered why the mother slowly turned white after beeing orange for 2 years.. It seems to be a genetic thing especialy long tailed (comets) are prone to loos pigment at an early age. Her ofspring that turned white already did it in the first year while some other siblings still are simply black and others again already strikingly orange. And all of them live together under same conditions.

I know color can be enhanced and prolonged with a special diet. I gues something like high Carotene content diet. But do not realy know, mine just get regular food.. That's also how commercial breeders color their new borns ASAP. Never seen a natural colored ordenary goldfish in the shop, i know they all are ready for sale at 1 year old and gold as can be. I still have black/natural colored ones older than a year..


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## rebel

The spectrum and light intensity will all have an effect on algae. LEDS have their own quirks on both those factors.

While spectrum most likely matters for algae growth, my feeling is that it is only one of the 100s (maybe 1000s) of variables that may matter. I would seriously doubt that it would be easy to isolate spectrum as a variable easily without years of research.

One of the good features of LED is that most will have dimmers which should deal with the intensity issue. In fact you should not buy a LED without a dimmer. Lets force manufacturers to include them for the benefit of all beginners.


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## Barbara Turner

rebel said:


> In fact you should not buy a LED without a dimmer. Lets force manufacturers to include them for the benefit of all beginners.



I'd second that, a long with a timer.


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## kirk

Well i was always happy with our maxspect razor.


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## rebel

kirk said:


> Well i was always happy with our maxspect razor.


As long as it includes a dimmer.


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## kirk

That's what was great about it being able to adjust the percentages. Wish I'd shipped it to nz with me i miss aqua scaping.


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## mow said

My take on this is leds are more powerful than tubes thats a fact. Let me make this simple as i can. I started my tank with a diy led and was using 60w 6500k + 10000k full blast for 8 hours. I did run into some alage issues, Then i reduced it to 5 hours all the algae was gone. Over 2 months i ramped it up to 8 hours with no issues. 8 months later i added more leds 83w in total and lenses too :

Red 12 leds/ 12%
Blue 12 leds/ 12%
Green 12 leds/ 12%
3200k led 14 leds/ 18%
6500k led 13 leds/ 21%
10000k led 20 leds/ 25%
*83w total*
plus and i have them running 10 hours with zero algae issues. I only do 35 percent water change a week. To me it seems allot of people tend to buy these led units and run into algae issues because they do not let plants adjust to the lighting. As @rebel said you shouldn't buy leds without dimmers and i agree with him.



This video i dunno how accurate the par reading are but his using leds with 300 PAR on the substrate level and about a 1000 par a the surface level with zero algae issue. So to make this short and simple buy a unit with a dimmer and adjust levels slowly.


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## Barbara Turner

mow said said:


> i dunno how accurate the par reading are but his using leds with 300 PAR on the substrate level and about a 1000 par a the surface level with zero algae issue.



300par is very high, The guy must be a god at balancing everything perfectly on a knife edge. 
Would have been nice to read his section on algae control, but looks like his website is down. 
The plant colours are stunning, especially the echinodorus purple Knight. 

I reckon I'd need 500w of Led lighting to hit 300par (based on 1.2m long tank with light at 60cm off gravel) I'm not sure if there is a more accurate calculator out there. 
We could have a sweep stake on how many hours before everything goes green. 

I'm looking at upgrading my DIY light soon, switching to (separate Red, Green, Blue and white  LEDs) 
Flat out it will hit about 300 watts but I won't get close to that when I've fine tuned the colour. 

It's taken a long time play with colours calculation software to get the colour plaques and CRI value to something I'm happy with, started off very purple.


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## zozo

Here a nice complete read about LED light.. 

https://www.waveformlighting.com/aquarium

https://www.waveformlighting.com/horticulture

Also see site navigation for other explainatory links.


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## tiger15

Barbara Turner said:


> 300par is very high, The guy must be a god at balancing everything perfectly on a knife edge.
> 
> 
> 
> 
> 
> 
> I agree.  300 PAR is too high to be believable in artificial light.  I measured 300 PAR at my window morning direct light.  For high tech high light tank, 100 to 200 PAR is about the maximum.
> 
> 
> 
> zozo said:
> 
> 
> 
> Here a nice complete read about LED light..
> 
> https://www.waveformlighting.com/aquarium
> 
> https://www.waveformlighting.com/horticulture
> 
> Also see site navigation for other explainatory links.
> 
> 
> 
> 
> Some info in the above links is misleading.  For example, the statement that chlorophyll absorbs light predominantly in the red range is inaccurate.  All light from blue, green to red spectrum, 400 to 800 no, are utilized by plants.  The info is provided from vendor’s web site which is more interested in selling their led product
> 
> What’s lacking is info on the role of uv light on plants and algae.  Plants can display uv in their flower to guide insect pollination.  Many inect, fish and reptiles can see uv light human can’t. I know that reptile keepers need to install uv light to keep their pet healthy.  My planted bowls by the window receive direct sunlight and don’t get bba.  Is it uv light despite glass filtering off most of it.
> 
> Click to expand...
Click to expand...


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## Barbara Turner

There is a very interesting paper on the affects on uvr on algae here. 

https://www.researchgate.net/public...n_in_Algae_and_aquatic_macrophytes_-_A_review

It looks like UV-B /C  in low doses would have harmful affects on most Algae species,
(Algae that naturally occurs at high altitude less so) 
 This matches what people have experienced with BBA being reduced on a window sill. 

I just get the feeling it also a case of how much do you want to stunt the growth of the other plants. 

If I got to the point that algae had completely taken over and I was at the point of throwing everything away, would I try a UVC germicidal lamps.. Probably.


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## rebel

For the DIY LED guys, they could add some UV-c? LEDS to their setups....to use on demand...


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## tiger15

Barbara Turner said:


> There is a very interesting paper on the affects on uvr on algae here.
> 
> https://www.researchgate.net/public...n_in_Algae_and_aquatic_macrophytes_-_A_review
> 
> It looks like UV-B /C  in low doses would have harmful affects on most Algae species,
> (Algae that naturally occurs at high altitude less so)
> This matches what people have experienced with BBA being reduced on a window sill.
> 
> .


I read the paper but don’t understand what are the findings.  Yes, UV light can harm some algae, but at what level.  UV can harm people too at high level and/ or duration, but low level is beneficial in making Vitamin D.  The same benefit harm effects could likely occur to plants and algae, but not discussed in the paper.

UVC is the most damaging form of UV, but never reach the earth surface.  It can be produced by mercury light, welding torch and UV sterilizer, so it’s unsafe to shine it onto the fish tank. 

https://share.upmc.com/2014/07/infographic-abcs-uv-difference-uva-uvb-uvc/

My observation is that direct sunlight can inhibit bba, gsa, possibly gda and others, yet promote green water, spirogyra and other filamentous algae.  So it’s not a black and white cut, and may not necessary be linked to UV light, just high light intensity.


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## Barbara Turner

I was surprised at how critical UVA and UVB when keeping both reptiles and amphibians, it’s a shame that there aren’t more terrariums out there with a half planted aquarium setups and aquatic plants as it would be interesting to know if they ever have algae problems.

I was surprised to read theat UV-A Can actually increase the rate of Algae growth

_"However, moderate levels of UV-A may stimulate photosynthesis and growth in both micro
and macroalgae (references in Xu and Gao, 2010). 
Gracilaria lemaneiformis (Rhodophyta) shows an increase relative growth rate in the presence of UV-A, while UV-B inhibited it (Xu and Gao, 2010)."_

UV-C is going to kill most if not all of the algae in the tank

_"UV-C is the most damaging range of the spectrum (Banaszak and Trench, 2001) but it is not of biological relevance because it is totally absorbed by the atmosphere (Banaszak and Trench, 2001; Holzinger and Lütz, 2006; Basti et al., 2009). Few studies have been carried out on the UV-C effect on established algal colonies. Borderie et al. (2011) showed that after various periods of UV-C exposure, the photosynthetic activity of algae was strongly decreased and even annihilated, which could be related to a degradation of their photosynthetic apparatus and pigment contents. After UV-C exposure, algal cells reinoculated on fresh medium were unable to proliferate (Borderie et al., 2011). UV-C radiation generates oxidative stress and genotoxicity effects. It is also known (Borderie et al., 2011) to induce programmed cel death (PCD) by a production of cyclobutane-pyrimidine dimers and DNA photoproducts, which are involved in cellular lethality, senescence and mutagenesis (references in Bordrerie et al., 2011)."_

UV-B is going to slow down algae growth

_"reducing  its  growth to  54%.  The lower  sensitivity  was  recorded  in Fucus vesiculosus. Makarov (1999) also described May as a  critical  period  for  algae,  which  were  highly affected by ultraviolet radiation during this month. The apical segments of the intertidal macroalga Hypnea musciformis  (Rhodophyta,  Gigartinales) cultivated in  vitro  free  of  UV  radiation  showed growth rates of 9.7% day-1, while algae exposed to UV-B grew only 3.2% day-1 (Schmidt et al., 2012)."_


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## Barbara Turner

rebel said:


> For the DIY LED guys, they could add some UV-c? LEDS to their setups....to use on demand..



UV- B and UV-C Leds  rocket up in price there are some really low powered ones "Output power: 0.3-0.9 mw, 0.5 to 1.5 mw" for £45 each  a 1watt UV-B LED is £400 https://www.ebay.co.uk/i/252329124368?chn=ps


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## Oldguy

I think that there were some early and to my mind cheap & nasty UVC units (not LEDs) that shone directly onto the surface of aquarium water and could be used for to investigate UV effects on algae.

 UVC is germicidal and will damage cells, plant or animal. However its effective germicidal  penetration into clean water is only about 2 inches at the most. The dimensions of the water annulus in most UVC units is nearer to 1 inch. Glass is opaque to UVB and UVC, but will transmit UVA. Some hydroponic LEDs claim to be broad spectrum ie IR through visible to UV.

I have never used them, though I do use broad spectrum visible units with additional small red/blue hydroponic LEDs light units. I have, so far, less algae than when I used mixed florescent tubes.

My tank receives no direct sun light and only low levels of ambient light. I built it into a chimney, bit of a sod to maintain. I view spots of bbg on Anubis leaves as the price of growing these plants with stem plants that require higher light levels. I just love the architectural qualities of near hand sized Anubis leaves.


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## tiger15

Mercury lamp gives off UVC and before glass cover is installed to block it, people were wondering why they got tan.  

I am wondering why UVC cannot penetrate more than 2 inch in clean water.  If blue light can penetrate water deeper than red light, logically more energetic UV lights can penetrate even deeper.


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## Oldguy

tiger15 said:


> UVC cannot penetrate more than 2 inch in clean water.


It can, but _effective germicidal_ penetration is the issue. However it depends on what you want to zap. Pond clarifiers may have a larger water annulus. UVA is the tanning type. UVC is skin death, but you do get a tan on short exposure. Arc welders V tan around the neck.


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## jaypeecee

Hi Folks,

Me again!

I've just read this thread and, unless I'm mistaken, there is much emphasis on UV light. I don't want to get into a debate regarding the question posed by the OP. But, if algae _is_ worse with LED lighting, then I would like to propose a possible explanation. Here on UKAPS, there is also a related thread:

https://www.ukaps.org/forum/threads/what-exactly-causes-bba.36674/

I would like to suggest that algae and cyanobacteria (BGA) growth may indeed be worse with aquarium LED lighting because these products invariably emit a lot of light in the green/yellow/orange/red part of the spectrum. In other words, from 500nm to 625nm. Please see the attached (first image).

Referring specifically to BBA, I understand this to be a form of red algae (rhodophyta). As such, it absorbs light peaking at 565nm. And 'white' LEDs emit a _lot_ of light at this wavelength. Please see the attached spectrum. Indeed, 'white' LEDs are designed to produce, well, er, white light to _illuminate_ things. It is white light precisely because it combines red, green and blue parts of the spectrum. I measured the spectrum of my own custom aquarium LED lighting fixture and no less than 50% of its output falls in the 500nm to 625nm band. Please see the attached (second image).

Now, turning to cyanobacteria, they contain a photosynthetic pigment known as phycocyanin. Its response to light peaks at around 620nm. And, here again, it can bask in the plentiful supply of light provided by white LEDs. From the attached graph, it can be seen that the colour of the phosphor(s) used in the LED shift the peak output of the emitted light.

Aquatic plants contain chlorophyll a and accessory pigments such as beta-carotene (orange colour). But, aquatic plants don't absorb much light in the green part of the spectrum, which is why they appear green. The exact amount of green light that plants (in general) absorb seems to vary according to the scientific literature that I've tried to understand!

I see a dilemma here in that we naturally want our tanks to look nice and this requires a particular spectrum. But this spectrum needs some adjustment in order to potentially reduce the likelihood of unwanted menaces such as BBA and BGA.

JPC


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## Zeus.

If a plant/moss/algae does well with a specific wavelength of photons and if LEDs have that output then they will do well, but how well depends on what other limiting factors are for the plant/moss/algae


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## jaypeecee

Zeus. said:


> If a plant/moss/algae does well with a specific wavelength of photons and if LEDs have that output then they will do well, but how well depends on what other limiting factors are for the plant/moss/algae



If I understand you correctly then, yes, I agree. Light alone does not make plants or moss or algae or cyanobacteria grow. Nutrients are required and that includes free nitrogen in the case of cyanobacteria. But, we only need to reduce/eliminate one of these to have an impact on the growth rate (or lack of) on any of these living organisms. As plants do not appear to need much light from 500nm to 625nm, then I suggest that's where we may want to consider focussing our attention. In the following thread, there are no less than 28 pages of discussion about what causes BBA:

https://www.ukaps.org/forum/threads/what-exactly-causes-bba.36674/

Forgive me if I'm mistaken (28 pages), but I don't think the lighting _spectrum_ is mentioned. And that's where I think some attention should be given. That's all.

JPC


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## zozo

jaypeecee said:


> Forgive me if I'm mistaken (28 pages), but I don't think the lighting _spectrum_ is mentioned. And that's where I think some attention should be given. That's all.



Indirectly it is mentioned, in some replies referring to this article

https://www.researchgate.net/public..._temperature_irradiance_pH_and_diurnal_rhythm

Where is stated that Freshwater Rhodophyta prefers to grow in shaded environments?  Now spectrum in Nm is not specifically mentioned. Not part of the investigation, i guess.  But as far as i did understand is that the light spectrum in the shadows is dominantly blue?


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## jaypeecee

Hi @zozo

Thanks for that. Unfortunately, I don't think the paper investigated the impact of lighting spectrum. But it does talk about eight freshwater red algae species occurring in low light. The BBA that I have had in my tank is present only where lighting is high. In shaded areas, there is no BBA whatsoever. After some digging around on https://www.algaebase.org, I learned that there is a species of red algae known as Rhodochorton, which grows in low light. But I was under the impression that the species to which we aquarists refer as BBA is something called Audouinella. Any algologists out there?

JPC


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## zozo

jaypeecee said:


> Any algologists out there?



I'm afraid not, they likely are as scarce as Broyoligist are. And i guess this is mainly because both plant species are a very ancient plant species in such a large diversity it is about impossible to determine the majority without a microscope and extended knowledge.

And regarding the light spectrum and what and how plants (macrophytes) use it is still fairly unknown. We have the means to determine that plant photosynthesis reacts to certain bandwidth between red and blue. For a long time, it was thought it only uses light between 400 – 700 nm and discards the rest. Not so long ago it was discovered that plants also use the far red between 750 - 850 nm. Scientists yet do not know if and what it does with the rest of the spectrum.

And not able to find any evidence for it, doesn't mean the plant doesn't have any use for it. Now i'm far from a scientist but my best guess is, we probably yet have no full understanding about what light actually is and how it is fully used in biological processes such as photosynthesis in living tissue. Most likely related that we also do not fully understand what life itself is.

For the rest, for us, hobbyist and what we experience in our aquariums is something far from universal. There are so many other environmental parameters we can not determine what could have an effect on how it grows.

For example, my light is not your light. And most likely depending on where you are on this planet the natural light you receive might be slightly different from the natural light i receive caused by atmospheric influences it needs to penetrate before it reaches our location. Then naming aquatic life forms that are underwater, this light also needs to penetrate the water this also has an effect on how its spectrum is filtered.

Something far to dynamic to determine and even further from to make it something universally applicable.  For me that is most likely the reason why the study paper i linked to neglects light spectrum entirely.


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## dw1305

Hi all, 





jaypeecee said:


> I learned that there is a species of red algae known as Rhodochorton, which grows in low light. But I was under the impression that the species to which we aquarists refer as BBA is something called Audouinella. Any algologists out there?





zozo said:


> I'm afraid not, they likely are as scarce as Broyoligist are


Phycologists are thin on the ground, the major issue is that all the Rhodophyta have a <"very complex life cycle">, with alternation of generation and different types of haploid and diploid spore. 



 

In <"the  BBA thread"> (on pages 20 and 21) there is a comment on names and some BBA images.

We were able to contact a leading expert (Phycologist) on red algae ,<"from the NHM">, and she said:

 "_It will either be an Audouinella or chantransia phase of Batrachospermum. If it came from an aquarium then it would probably be impossible to tell without DNA work.".
_
cheers Darrel


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## jaypeecee

zozo said:


> I'm afraid not, they likely are as scarce as Broyoligist are. And i guess this is mainly because both plant species are a very ancient plant species in such a large diversity it is about impossible to determine the majority without a microscope and extended knowledge.
> 
> And regarding the light spectrum and what and how plants (macrophytes) use it is still fairly unknown. We have the means to determine that plant photosynthesis reacts to certain bandwidth between red and blue. For a long time, it was thought it only uses light between 400 – 700 nm and discards the rest. Not so long ago it was discovered that plants also use the far red between 750 - 850 nm. Scientists yet do not know if and what it does with the rest of the spectrum.
> 
> And not able to find any evidence for it, doesn't mean the plant doesn't have any use for it. Now i'm far from a scientist but my best guess is, we probably yet have no full understanding about what light actually is and how it is fully used in biological processes such as photosynthesis in living tissue. Most likely related that we also do not fully understand what life itself is.
> 
> For the rest, for us, hobbyist and what we experience in our aquariums is something far from universal. There are so many other environmental parameters we can not determine what could have an effect on how it grows.
> 
> For example, my light is not your light. And most likely depending on where you are on this planet the natural light you receive might be slightly different from the natural light i receive caused by atmospheric influences it needs to penetrate before it reaches our location. Then naming aquatic life forms that are underwater, this light also needs to penetrate the water this also has an effect on how its spectrum is filtered.
> 
> Something far to dynamic to determine and even further from to make it something universally applicable.  For me that is most likely the reason why the study paper i linked to neglects light spectrum entirely.



Hi @zozo 

Thanks for the feedback.

JPC


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## jaypeecee

Hi @dw1305 

I can't see the image you attached. It has a yellow Warning label. Just thought I'd let you know.

JPC


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## Matt @ ScapeEasy

zozo said:


> Most likely related that we also do not fully understand what life itself is.



42


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