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Is Algae worse with LED lighting?
- Thread starter Barbara Turner
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Barbara Turner
Member
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.
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.
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.
Barbara Turner
Member
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)."
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)."
Barbara Turner
Member
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
Oldguy
Member
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.
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.
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.
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.
Oldguy
Member
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.
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
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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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
zozo
Member
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? 🙂
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
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
zozo
Member
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 all,
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
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
Matt @ ScapeEasy
Member
42
