Controlling the Light Spectrum to Limit Algae Growth

[RaymondL]

I'm using the stock light fixture on Fluval's EVO 13.5 tank, and having read the *fantastic* review done by Nate at Spec-Tanks (https://spec-tanks.com/fluval-evo-13-5-saltwater-nano-aquarium-review/), I'm considering whether I should scrap the stock and get a light that allows for control of the LED spectrum.

Shown below is the analysis of the stock light fixture:

Photosynthesis uses both ends of the spectrum, and if I'm not mistaken the tail end of the spectrum is not needed in reefing, and given that this light is not configurable, I'm stuck with the preset 600-700nm range of that intensity.

Reaching out here to folks who know more about light spectrum and its relationship to algae/photosynthesis and corals - should I be concerned with this stock light? FYI: I'm fully going to be stocking soft corals only, and perhaps some low PAR requiring LPS in the long run. My thought is to limit the amount of algae growth, and if this light might be contributing to it, I would like to replace it.

Thanks

 

[ISpeakForTheSeas]

I'm using the stock light fixture on Fluval's EVO 13.5 tank, and having read the *fantastic* review done by Nate at Spec-Tanks (https://spec-tanks.com/fluval-evo-13-5-saltwater-nano-aquarium-review/), I'm considering whether I should scrap the stock and get a light that allows for control of the LED spectrum.

Shown below is the analysis of the stock light fixture:

Photosynthesis uses both ends of the spectrum, and if I'm not mistaken the tail end of the spectrum is not needed in reefing, and given that this light is not configurable, I'm stuck with the preset 600-700nm range of that intensity.

Reaching out here to folks who know more about light spectrum and its relationship to algae/photosynthesis and corals - should I be concerned with this stock light? FYI: I'm fully going to be stocking soft corals only, and perhaps some low PAR requiring LPS in the long run. My thought is to limit the amount of algae growth, and if this light might be contributing to it, I would like to replace it.

Thanks

Some people believe that by only using blue lighting, they will limit algae growth/give coral an edge to outcompete algae. I find these claims to be pretty dubious personally, as most algae species utilize blue light as well, but it's possible there may be some small anti-algal/pro-coral effects.

I have a couple of posts on the thread linked below* discussing using blue lighting for algae control that go into a bit more detail, but - to be brief - using lighting to control algae doesn't seem to be anywhere near as effective as many people make it out to be. It may help limit a few types of algae, but I personally wouldn't run all blue lighting to try and prevent algae - if I was going to run all blue lighting, it would be to get a good fluorescent pop from my corals.

* The thread: https://www.reef2reef.com/threads/w...olor-here-to-stop-algae.919937/#post-10338958

I haven't looked much into the tail ends of the spectrum, but a few people swear by infrared lighting as being beneficial to corals, and I know that UVA lighting does have a positive impact on the fecundity of at least a few animals (such as Ghost/Grass Shrimp). So, while the tail ends of the spectrum may not be needed, there may still be some benefit in providing them for your tank regardless.

 

[Dan_P]

I'm using the stock light fixture on Fluval's EVO 13.5 tank, and having read the *fantastic* review done by Nate at Spec-Tanks (https://spec-tanks.com/fluval-evo-13-5-saltwater-nano-aquarium-review/), I'm considering whether I should scrap the stock and get a light that allows for control of the LED spectrum.

Shown below is the analysis of the stock light fixture:

Photosynthesis uses both ends of the spectrum, and if I'm not mistaken the tail end of the spectrum is not needed in reefing, and given that this light is not configurable, I'm stuck with the preset 600-700nm range of that intensity.

Reaching out here to folks who know more about light spectrum and its relationship to algae/photosynthesis and corals - should I be concerned with this stock light? FYI: I'm fully going to be stocking soft corals only, and perhaps some low PAR requiring LPS in the long run. My thought is to limit the amount of algae growth, and if this light might be contributing to it, I would like to replace it.

Thanks

The dream of controlling algae growth while keeping photosynthetic coral with light spectrum is highly unlikely. Algae growth control is achieved through physical removal by the aquarist or snails. Algaecides may help.

 

[Jekyl]

Algae isn't a bad thing. It's a normal process we go through and it's a healthy part of a maturing tank. It will come, then it will go. If wanting to get a new light, get one with coral in mind, not algae.

 

[Sdot]

The key to your issue is not altering light spectrum but introducing competition and predators. A good cleanup crew will serve you well, starting with pods....

 

[RaymondL]

Some people believe that by only using blue lighting, they will limit algae growth/give coral an edge to outcompete algae. I find these claims to be pretty dubious personally, as most algae species utilize blue light as well, but it's possible there may be some small anti-algal/pro-coral effects.

I have a couple of posts on the thread linked below* discussing using blue lighting for algae control that go into a bit more detail, but - to be brief - using lighting to control algae doesn't seem to be anywhere near as effective as many people make it out to be. It may help limit a few types of algae, but I personally wouldn't run all blue lighting to try and prevent algae - if I was going to run all blue lighting, it would be to get a good fluorescent pop from my corals.

* The thread: https://www.reef2reef.com/threads/w...olor-here-to-stop-algae.919937/#post-10338958

I haven't looked much into the tail ends of the spectrum, but a few people swear by infrared lighting as being beneficial to corals, and I know that UVA lighting does have a positive impact on the fecundity of at least a few animals (such as Ghost/Grass Shrimp). So, while the tail ends of the spectrum may not be needed, there may still be some benefit in providing them for your tank regardless.

Thanks and for the link. Considering the natural setting of reefs/oceans and the Sun/Sunlight, there is no selection of certain wavelengths in nature, so one would think that have a full spectrum light in a tank shouldn't be that damaging - I wonder if trying to chase down the perfect lighting condition in our tank can introduce more a negative impact - this is were I think 'trial and error' comes into play until we lock it in what works - each of our tanks are different, so there really can't be a definitive lighting profile that works for all.

 

[RaymondL]

Thanks for all the replies - I do understand that controlling algae is more than just the lighting aspect; however, my thought is on Fluval's stock light fixture, which can't be adjusted unlike for example an AI Prime HD - Fluval's fixture includes and has an elevated light concentration between 600-700nm range. From a 'scientific' point of view and what I'm chasing after if by limiting this range, would there be a less presence of certain algae in the tank.

 

[Bucs20fan]

IME algae will grow from light seeping in from a window in a completely dark room, mostly regardless of spectrum, if there are phosphates and some light, algae will grow. Its part of all of our tanks, how we manage this algae separates it from being a part of the reef to nuisance.

 

[Jekyl]

Thanks for all the replies - I do understand that controlling algae is more than just the lighting aspect; however, my thought is on Fluval's stock light fixture, which can't be adjusted unlike for example an AI Prime HD - Fluval's fixture includes and has an elevated light concentration between 600-700nm range. From a 'scientific' point of view and what I'm chasing after if by limiting this range, would there be a less presence of certain algae in the tank.

The Kessel I have are already tuned to not have the spectrums you're discussing. Algae was still awful through the ugly phase. While reducing different spectrums can help, it doesn't stop it.

 

[RaymondL]

The Kessel I have are already tuned to not have the spectrums you're discussing. Algae was still awful through the ugly phase. While reducing different spectrums can help, it doesn't stop it.

Thanks - that was the affirmation what I was looking for - having a light that can control the spectrum I mentioned doesn't negate algae.

 

[minus9]

Whether it's micro algae, macro algae or Zooxanthellae, they all require the same conditions to grow (light, nutrients, etc) so trying to control algae growth by limiting the spectrum is a complete waste of time and will have the save affect on corals. As mentioned earlier, algae growth is a result of limiting predators (consumers). Remove the herbivores on a reef and see what happens. I've never been on a reef that didn't have algae growing next to corals (same with cyano, etc) but that growth was limited based on the herbivores on that particular reef. Same applies with nutrient control (and numbers). So a better way at looking at algae control or nutrient levels would be to address the lack of predators/consumers of algae. People who try to reduce nutrient levels by reducing feedings, limiting input of nitrogen, lowering nutrient numbers, etc...will have a bad time with that strategy, because your corals require the same conditions as the algae you're trying to get rid of. The take-away is, you don't have an algae/nutrient problem, you have a herbivore problem.
You can manage nutrient/nitrogen input without restricting the building blocks that corals need, but it's a balance between input/export and herbivores. And to the point concerning lighting, yes, there are wavelengths that excel algae growth, but their reduction will have limited results in the end.

 

[Bpb]

Algae contains chlorophyll a just like corals do. I don’t know of any photosynthetic critters that don’t readily take in and use blue light.

 

[Don424]

Whether it's micro algae, macro algae or Zooxanthellae, they all require the same conditions to grow (light, nutrients, etc) so trying to control algae growth by limiting the spectrum is a complete waste of time and will have the save affect on corals. As mentioned earlier, algae growth is a result of limiting predators (consumers). Remove the herbivores on a reef and see what happens. I've never been on a reef that didn't have algae growing next to corals (same with cyano, etc) but that growth was limited based on the herbivores on that particular reef. Same applies with nutrient control (and numbers). So a better way at looking at algae control or nutrient levels would be to address the lack of predators/consumers of algae. People who try to reduce nutrient levels by reducing feedings, limiting input of nitrogen, lowering nutrient numbers, etc...will have a bad time with that strategy, because your corals require the same conditions as the algae you're trying to get rid of. The take-away is, you don't have an algae/nutrient problem, you have a herbivore problem.
You can manage nutrient/nitrogen input without restricting the building blocks that corals need, but it's a balance between input/export and herbivores. And to the point concerning lighting, yes, there are wavelengths that excel algae growth, but their reduction will have limited results in the end.

Whether it's micro algae, macro algae or Zooxanthellae, they all require the same conditions to grow (light, nutrients, etc) so trying to control algae growth by limiting the spectrum is a complete waste of time and will have the save affect on corals. As mentioned earlier, algae growth is a result of limiting predators (consumers). Remove the herbivores on a reef and see what happens. I've never been on a reef that didn't have algae growing next to corals (same with cyano, etc) but that growth was limited based on the herbivores on that particular reef. Same applies with nutrient control (and numbers). So a better way at looking at algae control or nutrient levels would be to address the lack of predators/consumers of algae. People who try to reduce nutrient levels by reducing feedings, limiting input of nitrogen, lowering nutrient numbers, etc...will have a bad time with that strategy, because your corals require the same conditions as the algae you're trying to get rid of. The take-away is, you don't have an algae/nutrient problem, you have a herbivore problem.
You can manage nutrient/nitrogen input without restricting the building blocks that corals need, but it's a balance between input/export and herbivores. And to the point concerning lighting, yes, there are wavelengths that excel algae growth, but their reduction will have limited results in the end.

What predators are you referring to? I'm getting back to marine which I was in for 20 years and then took a turn to freshwater for the past 2 years.

 

[Don424]

Whether it's micro algae, macro algae or Zooxanthellae, they all require the same conditions to grow (light, nutrients, etc) so trying to control algae growth by limiting the spectrum is a complete waste of time and will have the save affect on corals. As mentioned earlier, algae growth is a result of limiting predators (consumers). Remove the herbivores on a reef and see what happens. I've never been on a reef that didn't have algae growing next to corals (same with cyano, etc) but that growth was limited based on the herbivores on that particular reef. Same applies with nutrient control (and numbers). So a better way at looking at algae control or nutrient levels would be to address the lack of predators/consumers of algae. People who try to reduce nutrient levels by reducing feedings, limiting input of nitrogen, lowering nutrient numbers, etc...will have a bad time with that strategy, because your corals require the same conditions as the algae you're trying to get rid of. The take-away is, you don't have an algae/nutrient problem, you have a herbivore problem.
You can manage nutrient/nitrogen input without restricting the building blocks that corals need, but it's a balance between input/export and herbivores. And to the point concerning lighting, yes, there are wavelengths that excel algae growth, but their reduction will have limited results in the end.

what kind of consumers are you referring to? I was in salt for 15 years & I'm getting back into marine after 2 years of doing fresh water. your patience with me would be appreciated. thanks

 

[minus9]

Predators of algae, my goofy take on herbivores. Tangs, snails, reef safe hermits (scarlets or micro hermits), conches, etc. It really depends on the size of your tank, but utility fish and invertebrate herbivores are your best defense in regards to algae.