Reducing white light, effect on coral?

[Stuckita]

Hey everyone, I have been having some algae issues and recently did some big water changes to bring down nutrients. I was watching some videos last night of some pretty great tanks that were running no to low white light. I currently have a 13hr light period with whites at 25% for about 6hrs. I am considering reducing that to 2-3hrs or removing it entirely?

I use a noopsyche light the peak lighting period is 12-6pm and the total photoperiod is 8am to 9pm.
Peak is
Whites: 25%
Blue 1: 100%
Green: 15%
Violet: 40%
Blue 2: 100%
red: 10%

This produces roughly 350 PAR up top and 250 on sand bed. Mixed reef with torches, montis, stylo, birds, hammers, zoa, goni, ect

If I reduce light will it cause growth to stop?

 

[Mr. Mojo Rising]

The only way to stop algae growth is to control the import/export ratio. Filtration and water changes should be enough to handle the nutrient export, if not, then need more filtration (or less bioload).

 

[Stuckita]

The only way to stop algae growth is to control the import/export ratio. Filtration and water changes should be enough to handle the nutrient export, if not, then need more filtration (or less bioload).

I think I should be good there now, it's relatively stable just elevated. Running filter floss/refugium. Removed the skimmer as it was overkill. Could white light slow growth of some coral? Or should I leave as is?

 

[Mr. Mojo Rising]

I think I should be good there now, it's relatively stable just elevated. Running filter floss/refugium. Removed the skimmer as it was overkill. Could white light slow growth of some coral? Or should I leave as is?

I will be interested to hear others comments, but I would leave it as it.

Algae is the result of nutrients, lighting, poor flow, lack of clean up crew, immature tank, not enough biodiversity, etc... so many influences that I cannot agree that changing just one thing will have an impact. Thats just my opinion though

 

[skey44]

What are your nutrient levels? Pic of tank?
I would run the skimmer if you are having to do large water changes for elevated nutrients, let the filter do the work for you.
I personally run 3-4 hours of “white” light during the day and transition to mostly blue/violet for the evening. That is working well for me.

 

[Dkmoo]

Algae is the result of nutrients, lighting, poor flow, lack of clean up crew, immature tank, not enough biodiversity, etc... so many influences that I cannot agree that changing just one thing will have an impact

This

Spectrum by itself does have an impact bc algae generally use only longer spectrums and corals has the ability to use fuller spectrums by regulating it's zoox and cfp levels. All the talk about blue light = best for coral is more for the purpose of coloration bc it promotes the activation of the CFPs that make the corals "pop" and floures. Coral health and growth generally speaking is easier to achieve on wider spectrum.

Last thing to consider is that "white" also contains blue spectrum so if dialing it down you'd need to dialing blue up more to maintain the same PAR output, which doesn't look like you can do since ur blue is already maxed.

Given than your white is already at 20, reducing it further is not going to have any meaningful impact to your original issue.

 

[Troylee]

I’ll never understand this! Nothing beats a 6500k metal halide at growing coral and I don’t care what anyone says! Are the colors pretty? Not at all! Washed out and brown! But they grow crazy fast lol… once the corals are to the size of your liking then change it up to 20k or leds etc and bring that color on! Or you have the best of both worlds and run a 14k scenario with led’s, t5’s or halides or what ever your little heart desires! White lighting does not cause algae and who ever coined that term has zero clue what they’re talking about lol…

 

[zerozero]

I have a Noopysche K7 pro 3

I'd consider a two pronged solution:

1. Remove the reds and greens for a month. Your corals don't need them.
2. Increase your algae-eating CUC; turbo snails, a conch and hermits (if you want crabs)

See where you are after a month.

 

[Stuckita]

What are your nutrient levels? Pic of tank?
I would run the skimmer if you are having to do large water changes for elevated nutrients, let the filter do the work for you.
I personally run 3-4 hours of “white” light during the day and transition to mostly blue/violet for the evening. That is working well for me.

Hey there, sorry on the delay, wanted to take some recent tests and get some pics (tank still waking up).

Current Nitrate 11, phosphate 0.04,
Previous Nitrate 25+, phosphate 0.1 I performed two 30% water changes over the last 2 weeks.

Pics aren't great! I seem to have hair cyana/dinos (more or less under control), but then hair algae that has been hard to get rid of, but relatively weak (turkey baster can get some of it off)

 

[Stuckita]

I have a Noopysche K7 pro 3

I'd consider a two pronged solution:

1. Remove the reds and greens for a month. Your corals don't need them.
2. Increase your algae-eating CUC; turbo snails, a conch and hermits (if you want crabs)

See where you are after a month.

Already completed step 2. Interesting about step 1. Not needed at all? I can remove permently. Is violet a good spectrum (say if I dropped whites to 20% red/green off, and upped violet to 100%)

 

[Stuckita]

This

Spectrum by itself does have an impact bc algae generally use only longer spectrums and corals has the ability to use fuller spectrums by regulating it's zoox and cfp levels. All the talk about blue light = best for coral is more for the purpose of coloration bc it promotes the activation of the CFPs that make the corals "pop" and floures. Coral health and growth generally speaking is easier to achieve on wider spectrum.

Last thing to consider is that "white" also contains blue spectrum so if dialing it down you'd need to dialing blue up more to maintain the same PAR output, which doesn't look like you can do since ur blue is already maxed.

Given than your white is already at 20, reducing it further is not going to have any meaningful impact to your original issue.

How does violet come into play? Currently whites are at 25%. I find the noospyche light to have a big jump between 19% and 20% white - it's visually noticeable. I could drop the whites and up the violet?

 

[zerozero]

Already completed step 2. Interesting about step 1. Not needed at all? I can remove permently. Is violet a good spectrum (say if I dropped whites to 20% red/green off, and upped violet to 100%)

I wouldn't say permanently, just for a month till yo get your algae problem under control. The white light has all the colours of the rainbow, but if you're looking to have a period in the day where your tank looks natural, it'll be hard to achieve without the reds and greens.

Your tank looks lovely, btw.

 

[Stuckita]

I wouldn't say permanently, just for a month till yo get your algae problem under control. The white light has all the colours of the rainbow, but if you're looking to have a period in the day where your tank looks natural, it'll be hard to achieve without the reds and greens.

Your tank looks lovely, btw.

Sounds good, and thank you very much! It's my first tank ever (salt or fresh) and has been quite the learning curve over the last year haha. I made a lot of beginner mistakes but have learned a lot - especially with regards to myself and patience ;)

 

[Randy Holmes-Farley Verified Community Expert]

I would challenge the prevailing simple opinion that algae cannot thrive on UV and blue. The actual data that I have seen shows a more complex picture that varies by algae species.

This paper shows that while red algae photosynthesizes poorly at 440 ppm (about 1/2 to 1/4 as well as at its peak at 560 nm) that green algae such as Ulva and Coilodesme actually photosynthesize best at 440 nm compared to all other wavelengths from 420 to 720 ppm. There is a second peak at 675 ppm that is smaller than the one at 440 ppm.

https://pmc.ncbi.nlm.nih.gov/articles/PMC2147193/