# Light colour & algae



## idris (21 Aug 2021)

Is there any colour light that is less prone to helping algae? Without working things out scientifically, I'm wondering about purely green light (as I think that what's reflected from green leaves... right?) 
As much as anything I'm hoping to extend the time I can watch my tank without it causing algae growth.


----------



## PARAGUAY (22 Aug 2021)

I think its more to do with a balance of your lighting than this light or that light to avoid algae. I always use cheap t5 ( see James C in lighting)tubes and recently budget end nicrew eg LED lights . Seen quite a few examples of more expensive lights with just the same algae issues. Low energy aquariums can have and better for it long photoperiods. Use floating plants is good way to go.Personally go for a pleasing light to your eye.The question about greens and lighting is a technical one. One of our lighting gurus might help


----------



## ceg4048 (22 Aug 2021)

I agree with paraguay. There is no color you can use that will avoid algae. Algae is cause by too much light intensity of any and all colors. If the intensity is low enough then the lights can be on for a long time.

Having said that you can give yourself more room for error with bulbs that do have a high green and yellow content. The old ADA bulbs (the NA bulbs) are very high in green/yellow which made the tank look bright to human eyes but were still had a low PAR output. There were (and probably still are) however, ridiculously expensive. 
It's probably better to simply use the old school T8 fluorescent bulbs which doesn't cause much trouble. That's what folks used long ago and rarely suffered as much of these algal blooms. We now have access to LED fixtures which have wattage ratings which seem quite low by comparison - but folks simply do not realize how much more aggressive light intensity is produced for very low wattage. 

Cheers,


----------



## idris (23 Aug 2021)

Are cheap, domestic/ ebay (green / RGB) IP65 LED strips relatively "intense" compared to aquarium specific LEDs. My gut says they ought to be less "intense". But I've no idea how 1hr with something like that would compare with an hour of my iQuatics T5s. 
(Throw in a PWM driver from something like an Arduino clone and ... well ... I'm ar least partially out of my depth. I have some components lying around, but no PAR meter.)


----------



## ceg4048 (23 Aug 2021)

Few have any idea, without an objective measuring device, which unit has higher intensity, whether labeled as aquarium specific or otherwise.
Without a PAR meter much of what you see, or much of what you think you see...can easily be an illusion.
More importantly, the advantage of an LED, as long as you spend enough money, is to have a dimmer. If you're a good DIYer then you can cut the wires and assemble it to your own dimmer.

Cheers,


----------



## akwarium (24 Aug 2021)

Many types of algae can use green light,  Rhodophyta en Cyanobacteria have phycobilisomes to catch that part of the spectrum. That is why they don't appear to be green. 

If you change your lightning algae usually appear, but with proper maintenance (cleaning the algae away) and care (fertilizing the plants) plants will adapt and make algae disappear again.  I light my tanks for 10 - 12 hours a day, because I don't like looking at a dark tank.  I have massive outbreaks of algae 7-10 days after setting up a new tank, less light (lower intensity/shorter period) will slow the growth rate of algae down and make it more manageable for sure, but after a few weeks things will improve when plants start growing and take over.  In my experience it does not matter if you have low or high light, low or high co2,  full EI or lean dosing, as long as you keep the levels consistent, given time plants will beat the algae.


----------



## ceg4048 (27 Aug 2021)

akwarium said:


> Many types of algae can use green light, Rhodophyta en Cyanobacteria have phycobilisomes to catch that part of the spectrum. That is why they don't appear to be green.


That is true and plants also use green light because they have the same light gathering proteins as algae and cyanobacteria. In fact, green light is used in conjunction with the other wavelengths to deliver those photons deeper which allows these proteins that are below the surface to obtain more light.

The fact that Rhodophyta and Cyanobacteria are capable of using green should NOT be construed to mean that if your light has green this will cause algae.

Cheers,


----------



## akwarium (30 Aug 2021)

ceg4048 said:


> That is true and plants also use green light because they have the same light gathering proteins as algae and cyanobacteria. In fact, green light is used in conjunction with the other wavelengths to deliver those photons deeper which allows these proteins that are below the surface to obtain more light.
> 
> The fact that Rhodophyta and Cyanobacteria are capable of using green should NOT be construed to mean that if your light has green this will cause algae.
> 
> Cheers,



Well the proteins in plants and algae are not all exactly the same,  Chlorophyll A is universal but the other types of chlorophyll are not.  Phycobilisomes and the proteins they are made of are restricted to certain types of algae and cyanobacteria. Other chemicals like carotene and xanthophyll are found in both but not in all. So there are some differences,  but the end result is very similar.  And not relevant for our purposes at all.

it is indeed a widespread misconception that plants will grow better if provided with light in the wavelengths they can absorb best. this is not true,  it is only more energy efficient (to some extend)


----------



## idris (31 Aug 2021)

So more PAR is good for plant growth.
As I can't justify a PAR meter for purchase of a single light, is there any way to find low PAR lighting? (I can build an LED dimmer far more cheaply.) Every light I've seen advertised that mentions PAR seems to be sold on the basis of being good for plant growth, as opposed to good for evening viewing without plant (or algae) growth.
Or am I still missing the point?


----------



## dw1305 (1 Sep 2021)

Hi all, 


idris said:


> Every light I've seen advertised that mentions PAR seems to be sold on the basis of being good for plant growth, as opposed to good for evening viewing without plant (or algae) growth.


You can definitely use a dim light for tank viewing without getting anywhere near light compensation point (LCP) for any photosynthetic organism, plant or algae.  Our eyes are really good at adjusting to low light levels and <"subdued room lighting is only 100 to 200 lux">. 

cheers Darrel


----------



## ceg4048 (2 Sep 2021)

idris said:


> So more PAR is good for plant growth.
> As I can't justify a PAR meter for purchase of a single light, is there any way to find low PAR lighting? (I can build an LED dimmer far more cheaply.) Every light I've seen advertised that mentions PAR seems to be sold on the basis of being good for plant growth, as opposed to good for evening viewing without plant (or algae) growth.
> Or am I still missing the point?


It's exactly as Darrel mentions. LCP is a very low energy level and more PAR does not mean "better" growth. It simply causes "faster" growth. There are plenty of tanks using too much PAR where the rate of growth is fast, but the health of the plants is poor. Conversely, there are plenty of tanks lit with low light where the plants are very healthy. People very often confuse "fast" with "better".

Cheers,


----------



## jaypeecee (16 Oct 2021)

akwarium said:


> ...it is indeed a widespread misconception that plants will grow better if provided with light in the wavelengths they can absorb best. this is not true,  it is only more energy efficient (to some extend)...



Hi @akwarium

I'd be very interested in knowing more about this. From what I have read, it seems that action spectra and absorption spectra are closely correlated. And, since action spectra are quantifying photosynthesis activity by measuring oxygen released from a plant, would this not correlate with plant growth? Doesn't the rate of release of oxygen from a plant correlate with plant growth rate? Am I barking up the wrong tree?

If I'm not making myself clear, just say and I'll have another stab at this.

JPC


----------



## erwin123 (16 Oct 2021)

plants can grow pretty fast in the dark though one might not say its 'healthy' growth. I've seen it happen when I did a 72-hour blackout. Fast growth of some stem plants and aerial roots popping out. I've read of some terrestial plants when they are  shaded by other plants they try to grow as tall as possible to get sunlight, not sure if thats the explanation for growth during blackout periods as well.

As for the topic light spectra and photosynthesis, I found Bruce Bugbee's youtube videos absolutely fascinating (and of course, I have to credit UKAPS for introducing me to them)


----------



## jaypeecee (16 Oct 2021)

Hi @erwin123 

I, too, am a Bruce Bugbee fan. I have watched, listened and studied pretty much all of his video presentations.

JPC


----------



## akwarium (2 Nov 2021)

jaypeecee said:


> Hi @akwarium
> 
> I'd be very interested in knowing more about this. From what I have read, it seems that action spectra and absorption spectra are closely correlated. And, since action spectra are quantifying photosynthesis activity by measuring oxygen released from a plant, would this not correlate with plant growth? Doesn't the rate of release of oxygen from a plant correlate with plant growth rate? Am I barking up the wrong tree?
> 
> ...


yes you are right. 
But there are some remarks to be made, (note I'm just a hobbyist so by no means an expert)
Firstly plant growth is often looked at as the result of photosynthesis and therefor there is a focus on the absorption spectra of chlorophyll a and b.
That does not take carotenoids in account, which will also harvest energy.  Or Phytochromes which are most sensitive to deep and far red light and have a significant impact on how a plant grows and looks. (and are an important factor why plants stretch during a blackout)
Secondly there is a big difference between absorption of a single chlorophyll molecule and an entire leaf with several layers of cells all filled with chloroplasts, and entire plants made of several layers of leafs.  a leaf or plant can absorb 70% or even more of the green light, most of the red and blue will be absorbed in the top layers, but the green light penetrates deeper into the leaf tissue or canopy. There it will hit many more molecules of chlorophyll that will absorb it bit by bit. 
Lets not forget that once absorbed any photon is the same. The entire spectrum between 400 and 700 nm is called Photosynthetic Active Radiation, because it is.  Although red and blue's are absorbed to a higher degree then the colors in between, the difference is smaller then often assumed and lower leafs and chloroplasts deeper into the leave tissue might actually rely for most of there energy on greenish light. 
So using only red an blue light will mean that more of the light produced is also absorbed and converted in carbohydrates, which makes it more energy efficient. But for normal,  good looking and healthy plants, a full spectrum seems to be preferable.


----------



## dw1305 (2 Nov 2021)

Hi all, 


akwarium said:


> yes you are right.


Good explanation and better than I could manage.


jaypeecee said:


> From what I have read, it seems that action spectra and absorption spectra are closely correlated. And, since action spectra are quantifying photosynthesis activity by measuring oxygen released from a plant, would this not correlate with plant growth? Doesn't the rate of release of oxygen from a plant correlate with plant growth rate? Am I barking up the wrong tree?


Yes, oxygen release correlates very closely with CO2 incorporation. This is because for every molecule of CO2 that enters photosynthesis a molecule of oxygen (O2) is liberated. Plants are made of a carbon skeleton, and their growth is a measure of the net difference between CO2 absorbed and oxygen liberated. 

This net difference allows all <"aerobic life on earth"> to survive (and to initially develop). 






cheers Darrel


----------



## ceg4048 (2 Nov 2021)

akwarium said:


> So using only red an blue light will mean that more of the light produced is also absorbed and converted in carbohydrates, which makes it more energy efficient. But for normal, good looking and healthy plants, a full spectrum seems to be preferable.


Hello,
         This is not really true. You do not need full spectrum at all. This is the misconception that allows vendors to charge outrageous prices for their so called "full spectrum" bulbs. Plants have the ability to change the color of the incident light into other colors to fit their needs. Discussed and argued in the thread containing the post=> Fundamentals of Aquatic Lighting

We allow ourselves to be fleeced by the vendors because of our tacit agreement that spectrum is more important than it actually is. Hobbyists never really study this subject because it's a very difficult subject. As a result, we simply accept the opinions of the majority of others. The problem is, no one has actually ever proven that any "full spectrum" bulb grows plants any better than an ordinary bulb found in a supermarket or office building. Folks just assume that the majority opinion is correct without any data to show for it. In effect, might=right.

Was anyone aware, for example, that ADA bulbs were never "full-spectrum"? In fact, the bulbs are extremely high in green. So much so that the fluorescent bulbs actually have the model name "NA Green". No one argues the growth rate and health of their gallery tanks, yet, no one has ever questioned why their bulbs are not "full spectrum". Their tanks are low light because, as you mentioned, the green, although delivering lower PAR than blue, penetrates deeper into the tissue allowing it to reach the chlorophyll cells located further beneath the surface, thereby improving the quantum yield.

Cheers,


----------



## akwarium (3 Nov 2021)

ceg4048 said:


> Hello,
> This is not really true. You do not need full spectrum at all. This is the misconception that allows vendors to charge outrageous prices for their so called "full spectrum" bulbs. Plants have the ability to change the color of the incident light into other colors to fit their needs. Discussed and argued in the thread containing the post=> Fundamentals of Aquatic Lighting
> 
> We allow ourselves to be fleeced by the vendors because of our tacit agreement that spectrum is more important than it actually is. Hobbyists never really study this subject because it's a very difficult subject. As a result, we simply accept the opinions of the majority of others. The problem is, no one has actually ever proven that any "full spectrum" bulb grows plants any better than an ordinary bulb found in a supermarket or office building. Folks just assume that the majority opinion is correct without any data to show for it. In effect, might=right.
> ...


I did not say you need full spectrum.  I only said it seems to be preferable compared to only blue and red.  RGB is by no means full spectrum and still grows very nice plants.  For me any ordinary white LED is full spectrum enough (although they usually have very little violets, deep blues, cyan and reds, so technically it might not really be full spectrum)

for the past 6 years I use self made led lamps with one or more types/colors of good quality leds.   I experimented with adding 660nm reds, it should help aquarium plants to grow more compact, and maybe it does, but under the total amount of light plants will grow compact anyway, so I don't think it is really worth the trouble. (it does give a nice sunrise though).  I used 730nm far red to see if the emerson effect would speed up plant growth, I do think it had some effect.  but the tank was quite dimly lit,  In terms of energy efficiency maybe it was doing quite well, but unless you like a cheap brothel look, the esthetics were awful.

And aquarium lightning is not about maximum yield with a high energy efficiency, it is about esthetics. Since aquatic plants are not light demanding at all compared to most other plants and crops, just get a light that makes your tank look goed and your plants will probably be fine.  I enjoy all the discussions about spectra, and love reading about it, trying things for myself. Good fun, but practically a complete waste of time.


----------



## dw1305 (3 Nov 2021)

Hi all, 


akwarium said:


> For me any ordinary white LED is full spectrum enough (although they usually have very little violets, deep blues, cyan and reds, so technically it might not really be full spectrum)...........Good fun, but practically a complete waste of time.


That one for me, near enough is near enough. 

cheers Darrel


----------



## idris (3 Nov 2021)

akwarium said:


> I enjoy all the discussions about spectra, and love reading about it, trying things for myself. Good fun, but practically a complete waste of time.


As a lazy aquarist, this satisfies my confirmation bias.


----------



## oreo57 (3 Nov 2021)

dw1305 said:


> Hi all,
> 
> That one for me, near enough is near enough.
> 
> cheers Darrel





akwarium said:


> I did not say you need full spectrum.  I only said it seems to be preferable compared to only blue and red.  RGB is by no means full spectrum and still grows very nice plants.  For me any ordinary white LED is full spectrum enough (although they usually have very little violets, deep blues, cyan and reds, so technically it might not really be full spectrum)
> 
> for the past 6 years I use self made led lamps with one or more types/colors of good quality leds.   I experimented with adding 660nm reds, it should help aquarium plants to grow more compact, and maybe it does, but under the total amount of light plants will grow compact anyway, so I don't think it is really worth the trouble. (it does give a nice sunrise though).  I used 730nm far red to see if the emerson effect would speed up plant growth, I do think it had some effect.  but the tank was quite dimly lit,  In terms of energy efficiency maybe it was doing quite well, but unless you like a cheap brothel look, the esthetics were awful.
> 
> And aquarium lightning is not about maximum yield with a high energy efficiency, it is about esthetics. Since aquatic plants are not light demanding at all compared to most other plants and crops, just get a light that makes your tank look goed and your plants will probably be fine.  I enjoy all the discussions about spectra, and love reading about it, trying things for myself. Good fun, but practically a complete waste of time.


One needs to consider the upside down world of water.
High red content signals high light.
Low or no red signals low light.
The opposite of the terrestrial environment.

Also "we" aren't shooting for max dry weight or tweaking aromatics/vitamins ect.

Then there is the almost always limiting factor of CO2 compared to terrestrials.

The confusing use of " full spectrum" is just annoying. 





						3W 3 Watt Full Spectrum 380nm-840nm LG Chip LED Grow Light DC 3.2-3.4V 1A [KW-LG3GL] - US$1.00 : Topledlight
					

Topledlight 3W 3 Watt Full Spectrum 380nm-840nm LG Chip LED Grow Light DC 3.2-3.4V 1A [KW-LG3GL] - Product Description Specification Chip Brand: LG (please ignore the print mark on the pcb) Chip Size: 3535 Emitted Color: Full Spectrum Wavelength: 380nm ~ 840nm Power Output: 3W DC Forward Voltage...




					www.topledlight.com


----------



## jaypeecee (3 Nov 2021)

akwarium said:


> it is indeed a widespread misconception that plants will grow better if provided with light in the wavelengths they can absorb best. this is not true, it is only more energy efficient (to some extend)


Hi @akwarium 

It was your statement above that caught my attention. If, as you say, "it is only more energy efficient", does this not result in improved growth? And, by this, I mean in terms of height, width and sturdier growth? Surely, more efficient light/energy transfer from the light source to the receiving plant has got to be a positive thing - no? One observation I've made is that all natural processes have evolved to optimize the usage of energy. Why would photosynthesis be any different? Nature has an inherent intelligence that blows my mind.

JPC


----------



## jaypeecee (3 Nov 2021)

dw1305 said:


> Yes, oxygen release correlates very closely with CO2 incorporation. This is because for every molecule of CO2 that enters photosynthesis a molecule of oxygen (O2) is liberated. Plants are made of a carbon skeleton, and their growth is a measure of the net difference between CO2 absorbed and oxygen liberated.


Thanks, Darrel (@dw1305)

Simple answer, succinctly expressed.

Bravo!

JPC


----------



## jaypeecee (3 Nov 2021)

idris said:


> Is there any colour light that is less prone to helping algae? Without working things out scientifically, I'm wondering about purely green light (as I think that what's reflected from green leaves... right?)


Hi @idris 

It doesn't make sense to me to use aquarium lighting with spectrum peaks at around 565nm and/or 620nm. The first of these corresponds to peak sensitivity of red algae species (e.g. BBA). The second of these corresponds to peak sensitivity of Cyanobacteria (aka BGA). This is because each of these species contains accessory pigments - phycoerythrin and phycocyanin, respectively. In terms of lighting colour, these correspond to green/yellow and red, respectively.

As for the green part of the spectrum, a lot of green light is reflected from plants and that's why they appear green to us. But, green light penetrates deeper into the leaf.

JPC


----------



## oreo57 (3 Nov 2021)

Tweaking spectrum to control algae (any type) would be THE LAST consideration.
Certainly with green algae.
A MINOR argument w/ red algea may have "some"  History though has shown healthy growth and tank cleanliness are very effective.
Fun paper..








						PHOTOSYNTHETIC ACTION SPECTRA OF MARINE ALGAE
					

A polarographic oxygen determination, with tissue in direct contact with a stationary platinum electrode, has been used to measure the photosynthetic response of marine algae. These were exposed to monochromatic light, of equal energy, at some 35 points ...




					www.ncbi.nlm.nih.gov
				



One thing to note is chlorophyll is present though apparently err turned off. So much for natures " efficiency".

Pick a light that pleases you.


----------



## MichaelJ (4 Nov 2021)

jaypeecee said:


> It doesn't make sense to me to use aquarium lighting with spectrum peaks at around 565nm and/or 620nm


Hi @jaypeecee  I believe a lot of aquarium light corresponds to daylight (from slightly cooler to slightly warmer) and contains a lot of energy in the 550-650nm range - while it may not technically peak around there, it's still a pretty significant amount of the total energy. If you were to dial down that particular part of the spectrum your light and your tank wouldn't look very natural - so I don't really see that as a viable option. I think it's safe to say that any meaningful light, regardless of the spectral constituent, will promote algae if the tank is out of balance with regards to overall light intensity, , CO2, nutrients, waste etc. In my own tanks my light probably correspond to something slightly warmer than daylight or ~5500K (a huge lump in the 550-650nm range), and I don't have any algae to speak of.

Cheers,
Michael


----------



## akwarium (4 Nov 2021)

jaypeecee said:


> Hi @akwarium
> 
> It was your statement above that caught my attention. If, as you say, "it is only more energy efficient", does this not result in improved growth? And, by this, I mean in terms of height, width and sturdier growth? Surely, more efficient light/energy transfer from the light source to the receiving plant has got to be a positive thing - no? One observation I've made is that all natural processes have evolved to optimize the usage of energy. Why would photosynthesis be any different? Nature has an inherent intelligence that blows my mind.
> 
> JPC


I think you gave the answer yourself.  to be efficient in harvesting as much energy as possible from the light that hits them, plants(and algae) also need to absorb the light that is the hardest to adsorb.  Because the intelligence of nature(evolution), they have found ways to do so. So like said by me and others before, all wavelengths ,even the green, are absorbed pretty well, and more import  green has his own function in reaching deeper into the plant tissue.  Plants have been growing for 500 million years under the sun.  Trying to use a different spectrum is trying to outsmart nature. As you point out yourself the room for that is very limited.

Any plant depending its size, chlorofyll content, nutrient availability, carbon availability and all other kinds of physical and environmental factors, can produce a X amount of sugars per day. Therefore it needs X amount of photons(DLI). as long as those are provided the plant will grow at its best (given the circumstances).  Red and blue leds are at least in theory more efficient in producing light then white leds, and red and blue light are also absorbed a bit better. So you probably need a bit less leds/power to provide the X amount of photons: you save some energy.  
Complicating factor is that spectrum is also one of those environmental factors that determine how much photosynthesis there can/will be.


----------



## dw1305 (4 Nov 2021)

Hi all, 


akwarium said:


> Plants have been growing for 500 million years under the sun. Trying to use a different spectrum is trying to outsmart nature. As you point out yourself the room for that is very limited.


That is the one for me, only one sun and also <"all photosynthetic organisms contain chlorophyll a">. 

That chlorophyll a was originally in the <"free living cyanobacteria"> that are now in <"every eukaryotic photosynthetic plant cell"> as the organelle "a chloroplast".  

In the widest sense all photosynthetic organisms belong <"to the same clade">.


> .......... _Between 1 and 1.5 billion years ago [1, 2], eukaryotic organisms acquired the ability to convert light into chemical energy through endosymbiosis with a Cyanobacterium (e.g., [3, 4, 5]). This event gave rise to “primary” plastids, which are present in green plants, red algae, and glaucophytes (“Plantae” sensu Cavalier-Smith [6]). The widely accepted view that primary plastids arose only once [5] implies two predictions: (1) all plastids form a monophyletic group, as do (2) primary photosynthetic eukaryotes........_


In a more restricted sense all "green plants" (<"viridiplantae or chlorobionta">) are a monophyletic clade which have the same photosystems and basic physiology. 






Personally I think we are back to <"re-arranging the deck-chairs on the Titanic"> if we take too much time worrying about wavelengths and spectra. All you need is to have a light that provides <"enough PAR for your plants to reach LCP">.   

cheers Darrel


----------



## jaypeecee (5 Nov 2021)

dw1305 said:


> All you need is to have a light that provides <"enough PAR for your plants to reach LCP">.


Hi @dw1305 & Everyone

There isn't a problem with planted aquariums receiving _enough_ light. LED fixtures have taken care of that.

I'm more concerned about the potential effects of a sub-optimum lighting spectrum, too much PAR and photoperiod duration. In other words, potentially encouraging algae and Cyanobacteria growth. A good few aquarium lighting fixtures emit light at 625nm but this is unlikely to be of much benefit to plants. Not so for Cyanobacteria whose peak sensitivity occurs at this very wavelength. And it does appear that spectrum plays an important part in plant shape. According to Dr Bruce Bugbee of Apogee Instruments, blue light shrinks plants (or words to that effect). Or does this not apply in the aquatic environment?

If I've got all my facts wrong, then could you or anyone else please correct me?

JPC


----------



## idris (5 Nov 2021)

All fascinating stuff, and mostly beyond my level of knowledge. I just asked the question as I'd like to extend the illuminated hours so I can watch my tank without promoting algae, and was hoping eg green light might tick enough boxes.


----------



## jaypeecee (5 Nov 2021)

idris said:


> All fascinating stuff, and mostly beyond my level of knowledge. I just asked the question as I'd like to extend the illuminated hours so I can watch my tank without promoting algae, and was hoping eg green light might tick enough boxes.


Hi @idris

Green light would be my choice and not too bright. At least your plants will appear the colour that nature intended. That's assuming your plants are green, not red, yellow or some other colour. 

JPC


----------



## ceg4048 (5 Nov 2021)

dw1305 said:


> Personally I think we are back to <"re-arranging the deck-chairs on the Titanic"> if we take too much time worrying about wavelengths and spectra. All you need is to have a light that provides <"enough PAR for your plants to reach LCP">.


Exactly. This is the long and the short of aquarium lighting. What folks fail to understand is that LCP for plants is very low, somewhere between 10-20 micromoles. It's very unlikely that any bulb we use in the typical tank scenario produces energy below LCP at any location in the tank.


idris said:


> All fascinating stuff, and mostly beyond my level of knowledge. I just asked the question as I'd like to extend the illuminated hours so I can watch my tank without promoting algae, and was hoping eg green light might tick enough boxes.


As discussed earlier, use whatever bulb you want as long as you do not exceed the brightness that will trigger algal blooms.
No wavelength or spectrum will save you from algal blooms. Simply avoid using too many bulbs and if you elect to use an LED then make sure it comes with a controller that can vary the intensity. It is intensity that does the damage, not the wavelength.

Cheers,


----------



## jaypeecee (6 Nov 2021)

ceg4048 said:


> It is intensity that does the damage, not the wavelength.


So, does this mean that Dr Bruce Bugbee's statement 'blue light shrinks plants' does not apply to submerged plants? I realize that this example is not a case of plant _damage_ but it has to be considered as less than ideal. We don't really want blue light (or any other part of the PAR spectrum) _interfering_ with healthy growth. It's worth noting that blue light at 430nm has 50% more energy than red light at 645nm. In this respect, intensity and wavelength are inter-related. Furthermore, we should also take into account that red light is additionally attenuated by water even at just 30cm depth. 

JPC


----------



## jaypeecee (6 Nov 2021)

MichaelJ said:


> I think it's safe to say that any meaningful light, regardless of the spectral constituent, will promote algae if the tank is out of balance with regards to overall light intensity, , CO2, nutrients, waste etc.


Hi @MichaelJ 

Yes, I agree. I never meant to imply that lighting is the only factor in giving rise to algae or Cyanobacteria growth. Far from it. As a result of my experiments with Cyano, I can probably point to half a dozen factors that promote growth of the _Blue-Green Menace_ in our tanks. 

JPC


----------



## erwin123 (7 Nov 2021)

jaypeecee said:


> So, does this mean that Dr Bruce Bugbee's statement 'blue light shrinks plants' does not apply to submerged plants? I realize that this example is not a case of plant _damage_ but it has to be considered as less than ideal. We don't really want blue light (or any other part of the PAR spectrum) _interfering_ with healthy growth. It's worth noting that blue light at 430nm has 50% more energy than red light at 645nm. In this respect, intensity and wavelength are inter-related. Furthermore, we should also take into account that red light is additionally attenuated by water even at just 30cm depth.
> 
> JPC






2hr Aquarist cites the following article which suggests that different considerations apply to submerged plants (i.e. those that have an emersed and submersed form have a preference to be emersed?) : Ethylene-promoted Elongation: an Adaptation to Submergence Stress


I'll let the experts summarise it....


----------



## oreo57 (7 Nov 2021)

jaypeecee said:


> So, does this mean that Dr Bruce Bugbee's statement 'blue light shrinks plants' does not apply to submerged plants? I realize that this example is not a case of plant _damage_ but it has to be considered as less than ideal. We don't really want blue light (or any other part of the PAR spectrum) _interfering_ with healthy growth. It's worth noting that blue light at 430nm has 50% more energy than red light at 645nm. In this respect, intensity and wavelength are inter-related. Furthermore, we should also take into account that red light is additionally attenuated by water even at just 30cm depth.
> 
> JPC


Photosynthesis doesn't care about energy states.
Only photons.


> and that a minimum of eight photons of light must be absorbed in the process.


Doesn't matter about the " color".
Yea lots of blue light with little red can shrink internode elongation creating err stumpy stem plants but that is just a form not function thing. Not a matter of "health" Takes reef level of blue  to do it though.

ADDENDUM: Early in my led light building I experimented with color a bit. Crude and short but the resultst are fairly easy to see.
I ran some  large blue centric multichips for a brief period just to se the results..
Chips were "actinic" (royal blue) and high k white (14000?) 10w chips. Since they were cheap not going to swear by wavelengths or anything but the results are easy to see in the below pic.
Transition from wide to very short internodes is obvious. Health was same or arguably better but denser. Color was better but not really visible under that little red light.
Don't believe I ran the "experiment" for more than a few weeks if that.
Young tank so a mess but that's not why I'm posting it. :


----------



## ceg4048 (7 Nov 2021)

jaypeecee said:


> So, does this mean that Dr Bruce Bugbee's statement 'blue light shrinks plants' does not apply to submerged plants? I realize that this example is not a case of plant _damage_ but it has to be considered as less than ideal. We don't really want blue light (or any other part of the PAR spectrum) _interfering_ with healthy growth. It's worth noting that blue light at 430nm has 50% more energy than red light at 645nm. In this respect, intensity and wavelength are inter-related. Furthermore, we should also take into account that red light is additionally attenuated by water even at just 30cm depth.
> 
> JPC


Any high intensity light will damage aquatic plants if CO2 and nutrients are lacking. On the contrary, I've grown plants using Actinic lighting with no problems at all. You can't have your cake and eat it too. On the one hand you seem convinced blue light is bad for plants yet you also recognize that chlorophyll has a high response to blue and red. So just exactly what is your argument and what have you yourself tested? I see a lot of references to the work of others but you yourself have not actually put this information to practical use or demonstrated the validity of these hypotheses within the context of aquatic plants. Our conclusions are based on the empirical evidence of our tanks, not solely on the basis of someone else's experiments performed in a petrie dish.

You're also glossing over the fact that most of the light that plants or algae are exposed to in this world is blue. 
Additionally, the plants are never exposed only to blue. So whatever conclusion you wish to draw regarding shrinkage is irrelevant because there is no practical use of Dr. Bugbee's conclusion in our tanks.

Cheers,


----------



## jaypeecee (8 Nov 2021)

ceg4048 said:


> So just exactly what is your argument and what have you yourself tested? I see a lot of references to the work of others but you yourself have not actually put this information to practical use or demonstrated the validity of these hypotheses within the context of aquatic plants.


To date, I have simply been gathering information with the view of doing meaningful tests if and when I decide to purchase an Apogee SQ 520 PAR sensor. I have a perfectly adequate spectrometer. Aquatic lighting is a subject that interests me greatly. When the company, BML were in existence (now Omron _Fluence_), I designed the lighting fixture that is still over one of my tanks. Recently, I discovered that Dennis Wong also started out using BML lighting.

JPC


----------



## jaypeecee (8 Nov 2021)

ceg4048 said:


> You're also glossing over the fact that most of the light that plants or algae are exposed to in this world is blue.


No, I'm very much aware of that - for plants and algae in their natural habitat. But, we're trying to ensure optimum lighting for planted aquaria.


ceg4048 said:


> Additionally, the plants are never exposed only to blue. So whatever conclusion you wish to draw regarding shrinkage is irrelevant because there is no practical use of Dr. Bugbee's conclusion in our tanks.


I'm not drawing any conclusions about potential shrinkage caused by blue light. I'm simply asking questions on this forum and keen to hear what others have to offer. There may well be good reasons why Dr Bugbee's findings are not applicable to our tanks.

JPC


----------



## jaypeecee (8 Nov 2021)

oreo57 said:


> Photosynthesis doesn't care about energy states.
> Only photons.


Please tell us more.



oreo57 said:


> Yea lots of blue light with little red can shrink internode elongation creating err stumpy stem plants but that is just a form not function thing. Not a matter of "health" Takes reef level of blue to do it though.


So, Dr Bugbee's comments about blue light may indeed be applicable to the aquarium environment?  As I've never kept reef aquariums, can I assume that we would be unlikely to have sufficient PAR/PPF for blue light to be a problem?

JPC


----------



## ceg4048 (13 Nov 2021)

jaypeecee said:


> No, I'm very much aware of that - for plants and algae in their natural habitat. But, we're trying to ensure optimum lighting for planted aquaria.
> 
> I'm not drawing any conclusions about potential shrinkage caused by blue light. I'm simply asking questions on this forum and keen to hear what others have to offer. There may well be good reasons why Dr Bugbee's findings are not applicable to our tanks.
> 
> JPC





jaypeecee said:


> To date, I have simply been gathering information with the view of doing meaningful tests if and when I decide to purchase an Apogee SQ 520 PAR sensor. I have a perfectly adequate spectrometer. Aquatic lighting is a subject that interests me greatly. When the company, BML were in existence (now Omron _Fluence_), I designed the lighting fixture that is still over one of my tanks. Recently, I discovered that Dennis Wong also started out using BML lighting.
> 
> JPC


Well, I think the first thing you need to do for your tests is to establish a control tank using basic, ordinary bulbs. That's what we here have done and that's why we, after using different bulbs, after more than a decade, can report that there has not been any meaningful differences in growth performance, regardless of the type of bulb used. The reason is that there are many more important factors influencing growth performance, such as CO2 and nutrition, that far outweigh the influence of the bulb type being used. There may be colouration differences here and there, but there will not be a measurable difference based on spectra. In fact, it would be easy to see a difference in several tanks using different spectra and to then conclude that the differences were due to spectra, when in fact, the growth differences would be caused by variations in CO2/flow/distribution between the tanks. I supposed the tests would need to be performed multiple times so that the resulting data would be statistically relevant. At the end of the day, it won't really matter.

I have no idea about the specifications of BML lighting and just because Dennis Wong is using it that does not mean it is superior to other lighting. Dennis Wong is skilled enough to grow plants successfully using whatever lighting he chooses, so again, any BML Lighting testimonial means nothing more than typical hyperbolic marketing. One first has to be able to grow plants successfully regardless of the lighting technology in order to even begin to assess the impact of any spectral conditions. Have you accomplished this? Have you consistently produced planted tanks that are problem free? Have you been able to address problems in the tank and resolve them properly? Investigation of spectra before this task is tackled is putting the cart before the horse.
It seems to me that you have had problems in your tank and have immediately decided that the cause was due to spectrum while at the same time we here at this forum were advising you that no, your problem was due to insufficient nutrient, or CO2, or other factors that needed to be addressed. You chose however to use information from other websites that specifically offered advice to the contrary. Whether your problems were resolved is not clear.

Obviously you are free to carry on any experiments you wish, using any data you gather. No one disputes that. What many here object to however, is that our advice and information is immediately discarded as being faulty in favour of information from other websites, which you report as being more reasonable. Again, you have the freedom to follow any path you desire, but we also have the freedom to dispute the validity of the data presented in those other websites. Know this however; for many years we have investigated the topic of spectra, and while I now find it a tedious, certainly others may find it fascinating as you do, but the fact remains that test methods have to be stringent and above all, the method of control is paramount. You have not yet demonstrated an ability to consistently establish a control tank, i.e., a problem free tank. 

I repeat our position that a bulb's spectra has little or no bearing on plant growth or health compared to the effects of other factors in the realm of plant husbandry, such as CO2, PAR, nutrition and flow/distribution and spectra is certainly nothing that algae care about. With the exception of a few species, algal blooms are a direct result of nutritional deficiency syndromes that result in poor plant health. The species of algae that occur are a direct indicator of the deficient nutrient. Algal blooms are not a phenomenon that can be resolved by changing spectra, however, reduction of PAR has been shown to help alleviate the bloom.

Cheers,


----------



## jaypeecee (13 Nov 2021)

ceg4048 said:


> Well, I think the first thing you need to do for your tests is to establish a control tank using basic, ordinary bulbs. That's what we here have done and that's why we, after using different bulbs, after more than a decade, can report that there has not been any meaningful differences in growth performance, regardless of the type of bulb used.


If you've already done controlled experiments with aquarium lighting spectrum, has anyone done a write-up of your findings? If so, may I have a copy? That would be very helpful.



ceg4048 said:


> The reason is that there are many more important factors influencing growth performance, such as CO2 and nutrition, that far outweigh the influence of the bulb type being used.


Did your experiments include observation of algae and Cyanobacteria growth?


ceg4048 said:


> One first has to be able to grow plants successfully regardless of the lighting technology in order to even begin to assess the impact of any spectral conditions. Have you accomplished this? Have you consistently produced planted tanks that are problem free?


Following on from some failures, I am now managing to grow planted tanks with success.


ceg4048 said:


> It seems to me that you have had problems in your tank and have immediately decided that the cause was due to spectrum while at the same time we here at this forum were advising you that no, your problem was due to insufficient nutrient, or CO2, or other factors that needed to be addressed.


Over the years, I have rarely considered the part played by lighting spectrum. Insufficient nutrient and/or CO2 has not been a problem. Excess nutrients has occasionally been an issue.


ceg4048 said:


> You chose however to use information from other websites that specifically offered advice to the contrary


No such choice has been made. Why would I want to use information from A N Other website? Unless I'm mistaken, the only 'website' are the YouTube videos in which Dr Bruce Bugbee discusses his scientific research on plant lighting.


ceg4048 said:


> What many here object to however, is that our advice and information is immediately discarded as being faulty in favour of information from other websites, which you report as being more reasonable.


Is it really the case that "many here object to..."? I'm upset to hear that. Again, I'm not sure to which "other websites" you are referring.

To be continued...

JPC


----------



## jaypeecee (13 Nov 2021)

ceg4048 said:


> You have not yet demonstrated an ability to consistently establish a control tank, i.e., a problem free tank.


Am I being judged? I just don't get it.

JPC


----------



## Nick potts (13 Nov 2021)

Interesting discussion, light spectrum is something I have played with, though only for aesthetic reasons. I personally believe it makes little difference, at least in terms that would be useful to most tanks/keepers.



jaypeecee said:


> Am I being judged? I just don't get it.
> 
> JPC



I find your questions etc interesting (even if I don't agree for any reason) and I don't think most here would judge you for not being able to run a problem-free tank (who can??)


----------



## Hufsa (14 Nov 2021)

Maybe it comes down to differences in interest @ceg4048 and @jaypeecee .
It seems to me like you two are discussing something in which your end goals are not the same, so you cant find an agreement.

Correct me if im wrong but @jaypeecee it seems to me like you really enjoy getting into the smallest details of things, and figuring out exactly how things work.
To me that is perfectly okay, I am that way myself on some aspects of the hobby, and I think there is definitely room on the forum for threads that delve deeper into things.

While @ceg4048 , I have always benefited from your ability to "seperate the coffee from the froth" so to speak, to keep me grounded in practicality when my theoretical side is veering too far into the miniscule. (But I get the impression @jaypeecee is not looking to have his coffee de-frothed 😁 )

I do think beginners should be advised to stay away from the "froth" of the coffee, you got to nail the basics before you can experiment with the small things. Its so tempting as a newbie to get lost in the tiny details thinking that is whats gonna solve your problems, when it definitely is not. At least it is from my own experience.

I think we need to remember that we all enjoy the hobby in our slightly different ways 😊


----------



## jaypeecee (14 Nov 2021)

Hufsa said:


> Correct me if im wrong but @jaypeecee it seems to me like you really enjoy getting into the smallest details of things, and figuring out exactly how things work.


Hi @Hufsa 

Yes, ever since I was 'knee high', I have been fascinated about 'what makes things tick'. My entire working life was spent in a scientific environment - optoelectronics, professional audio (Dolby Labs) and, finally, professional radio communications.

JPC


----------



## jaypeecee (14 Nov 2021)

Nick potts said:


> Interesting discussion, light spectrum is something I have played with, though only for aesthetic reasons. I personally believe it makes little difference, at least in terms that would be useful to most tanks/keepers.


Hi @Nick potts 

What follows is just one of the reasons why I think there _may be_ more to aquarium lighting than aesthetics:

I have commented previously here on UKAPS that many aquarium lights contain LEDs that emit light at 625nm (red). I've never been able to understand this choice as it corresponds to the peak sensitivity of Cyanobacteria (aka BGA). My hunch was that the red LEDs should be emitting at 660nm. This corresponds to one of the peaks of chlorophyll a. It was, therefore, with some interest that I stumbled across the following just a couple of days ago:






						Planted+
					






					www.finnex.net
				




Finnex are not the only company that use 660nm LEDs. The German company below also use 660nm LEDs in some of their products:









						aquaLUMix LED-light-bar AMAZON-GROW
					

Compact light - ready-configured: AMAZON GROW colour variation is a bright, tropical light, with a focus on optimum plant growth, including Grow LEDs.




					www.ledaquaristik.de
				




Scroll down the above page until you get to the _cluster configuration_.

All the best.

JPC


----------



## jaypeecee (14 Nov 2021)

Nick potts said:


> I don't think most here would judge you for not being able to run a problem-free tank...


Hi again, @Nick potts 

As far as I'm concerned, none of us are here to_ judge_ others' tanks. That's what competitions are for. I'm not sure how anyone would be able to judge any of my tanks. I rarely post photos of them. Most of my recent tanks (with one exception) are running experiments of one form or another. That's what I enjoy doing. One of my main focuses has been on controlling Cyanobacteria with which I have had some success. I have another experiment running right now in which I'm getting to grips with the benefit of monitoring ORP (Oxidation-Reduction Potential). It's exciting making new discoveries and satisfies my scientific curiosity.

JPC


----------



## tiger15 (14 Nov 2021)

Stan510 said:


> I never had much of a Cyano problem for decades..none really until I set up aquariums that get some sunlight. This second time it got much more direct sun and I had a much more heavy growth of cyano. So,to get a handle on it...I put extra sheer curtains on the big window. Voila!..almost fixed. I also stopped weekly water changes on this big lo tech. Plants do even better since the water now had what they need. High Tech combine water changes with constant dosing. Feeding the fish is the main constant for me.
> Keep the filter cleaning on a regular basis is another big help.


The one setup I have persistent algae is my zero tech shrimp bowl exposed to direct afternoon sunlight.  My medium light high tech tanks have no algae, but I have the luxury of dosing excel or peroxide if I have to.  The type of visible algae in my shrimp bowl is limited to thread algae (Spirogyra) which I remove by hand as I can’t use chemical that will harm shrimp.  I think blue, purple and green cyno may be present in the substrate as I can see through the glass bottom, but do no harm as they are hidden underground.  I pull down a plastic grid behind the bowl to cut down sunlight in the afternoon that is helpful in reducing algae growth, but not enough to eliminate.


----------



## Nick potts (14 Nov 2021)

jaypeecee said:


> Hi @Nick potts
> 
> What follows is just one of the reasons why I think there _may be_ more to aquarium lighting than aesthetics:
> 
> ...



I don't have the expertise to comment on that, for me it is all about how the light looks to my eyes on a particular setup.



jaypeecee said:


> Hi again, @Nick potts
> 
> As far as I'm concerned, none of us are here to_ judge_ others' tanks. That's what competitions are for. I'm not sure how anyone would be able to judge any of my tanks. I rarely post photos of them. Most of my recent tanks (with one exception) are running experiments of one form or another. That's what I enjoy doing. One of my main focuses has been on controlling Cyanobacteria with which I have had some success. I have another experiment running right now in which I'm getting to grips with the benefit of monitoring ORP (Oxidation-Reduction Potential). It's exciting making new discoveries and satisfies my scientific curiosity.
> 
> JPC



I certainly agree, this is a very friendly forum 99.9% of the time

Do keep doing what you enjoy, that's what hobbies are for, I myself enjoy setting up tanks more than I do keeping tanks running for extended periods, so that's what I tend to do  Any insights into the dreaded cyano can only be a good thing AFAIAC.

I know ORP is something a lot of marine hobbyists measure, but this is usually as they are injecting ozone into the tanks.


----------



## MichaelJ (14 Nov 2021)

jaypeecee said:


> Most of my recent tanks (with one exception) are running experiments of one form or another. That's what I enjoy doing. One of my main focuses has been on controlling Cyanobacteria with which I have had some success. I have another experiment running right now in which I'm getting to grips with the benefit of monitoring ORP (Oxidation-Reduction Potential). It's exciting making new discoveries and satisfies my scientific curiosity.


Hi JPC, yes, and I personally think that is very admirable - keep that curious spirit going!

Cheers,
Michael


----------

