How important is red and green light?

[Lasse]

It's the sentence "part of the UV cycle" I never have heard of before. What is the UV cycle and how does blue and green wavelengths fit in there.

Sincerely Lasse

 

[Dana Riddle]

Has anyone researched Type I and Type II phytochromes and how they might enhance reproduction, chlorophyll synthesis, and other processes in respect to algal growth? These phytochromes absorb red or far-red light. I've never really looked at them as my focus has been on zooxanthellae which contain cryptochromes. It seems I read somewhere along the line that some zoox might contain phytochromes as well, but, gee, it's 4:45 am...

 

[jda]

Generally speaking, both TI and TII phytochromes do better from 450 to 800nm. However, this is not really what matters, IMO. The issue is will "more cause more?" Here you have to get anecdotal... and people with lights that have a good amount of this spectrum do not really grow algae much better than people who do not have as much... both can be troublesome (or fine) based on other factors.

Yes, algae will grow with red... but will a lot of red make it grow better? It does not seem like it when you observe many, many tanks and systems. If so, people never would have used 6500k and 10k MH or grow stuff under natural sunlight.

If you are running any kind of white light, then you have enough red to grow algae. If you are running anything above 425nm and certainly 450nm, then you still have enough light to grow algae. If you have algae issues and also keep coral, then look to other places than your lighting, IMO.

 

[BestMomEver]

Elizabeth, do a search for Dr Sanjay Joshi reef tank. He runs his Radions at 100% on all channels, but he has them up really high over the tank. While his tank is only now about 80% of what is was, I think that his tank is one of the best examples of what you can achieve with Radions, but he runs them differently than most people do. I think that EcoTech and even ReefBuilders have videos (err, advertisements) of his tank. You will not see very much algae... not any more than a normal tank of which all have some amount of algae and cyano.

I found his Radion settings and programmed them in just to see what they looked like. Maybe I’m used to a blue tank but I found his settings crazy bright. It’s stupid really cause I live in the sunny south and I know that things thrive under serious sunlight and if I had corals bleach it would be because I didn’t have them placed in the tank correctly, not because the “sun” was too bright. But, It still kinda scared me. When I turned the lights on with his settings the first thing I thought of was “bleached corals.” I chickened out and changed them back. If I didn’t have $1000s invested in coral I might try it.

 

[jda]

Do you have your panels way up high like he does? In any case, if you do want to change to any other settings, do it VERY slowly. There is not really much doubt that he has one of the best Radion tanks. When you also look at WWC does, they also keep the panels up high and turn them up - they are not nearly on the same level as Dr. Joshi, but they do a good job for a retail shop. They also have really large tanks and can have overlap from surrounding units help just a bit with fill and shadowing - this is not all that possible in smaller tanks. I think that there is something to what they are doing, but I do not use Radions, so I have no actual, personal experience.

In any case, did you see much algae when you looked at his tank photos?

 

[vetteguy53081]

It's the sentence "part of the UV cycle" I never have heard of before. What is the UV cycle and how does blue and green wavelengths fit in there.

Sincerely Lasse

I said cycle- better words " Wavelengths"

 

[Dana Riddle]

Generally speaking, both TI and TII phytochromes do better from 450 to 800nm. However, this is not really what matters, IMO. The issue is will "more cause more?" Here you have to get anecdotal... and people with lights that have a good amount of this spectrum do not really grow algae much better than people who do not have as much... both can be troublesome (or fine) based on other factors.

Yes, algae will grow with red... but will a lot of red make it grow better? It does not seem like it when you observe many, many tanks and systems. If so, people never would have used 6500k and 10k MH or grow stuff under natural sunlight.

If you are running any kind of white light, then you have enough red to grow algae. If you are running anything above 425nm and certainly 450nm, then you still have enough light to grow algae. If you have algae issues and also keep coral, then look to other places than your lighting, IMO.

I never discussed it with Nick at the old BuildMyLED, but they once marketed a 'refugium light' that was mostly red, if I remember correctly. Nick never did anything without a good reason... I visited him a few months ago and toured his manufacturing plant (Fluence Bioengineering) and saw rows of walk-in bio-chambers where they were testing effects of spectra. They partner with universities where plant tissues are then tested for various compounds. Not sure if they did this sort of thing with marine algae.

 

[Lasse]

This is my refugium light - have run it for two years - produce a lot of chaeto.

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Sincerely Lasse

 

[jda]

Again, I do not think that anybody is saying that red light will not grow algae, just that there is already enough for it to grow out of hand if you are using any other "white" light source.

 

[Lasse]

Again, I do not think that anybody is saying that red light will not grow algae, just that there is already enough for it to grow out of hand if you are using any other "white" light source.

I´m with you in this. Especially if you use low Kelvin LEDs.

Sincerely Lasse