Color of light that prevents algae growth?

oakengineer · 08/02/2016, 06:48 AM

I've been working on controlling GHA in my reef tank for about 1.5 years. I have tried everything from a chemistry standpoint. (I'm now down to 3 small lightly fed fish) So I think the lighting is kind of the last major thing to try. I have an Current LED light on my reef tank. Right now I'm running full intensity Actinic and White 12 hours a day. I have heard people suggest that I reduce the photo-period, the disadvantage of that approach is that based on when I'm at the house, I won't see the tank on in the evening if I change it. So I'm wondering if I can adjust the type of light to control algae. I think actinic is what the corals need, and I have heard white and read grows algae. So will turning white off, leaving actinic on keep the corals alive and keep algae from growing?

Bpb · 08/02/2016, 07:13 AM

Sadly it's not that simple. Hair algae can grow perfectly well in only blue light if water conditions are favorable for it. Algae is present due to a combination of factors including but not limited to tank age (the younger the worse), light levels, light spectrum (yes more red light can tend to grow more algae but it's not a deal breaker), available nutrients, bacterial levels, and presence or absence of herbivores. If any one of those factors of multiple are present, algae can and often does take a foot hold.

The current LEDs are pretty low power/low par compared to most more conventional or contemporary reef lighting so I'm not sure I would blame them as the sole culprit.

You CAN run a tank on purely blue and actinic light but I don't think it'll work as well as you may hope. Corals can grow under those conditions, especially those typically found in deeper regions, but they'll develop their best pigmentation and health under a more balanced full spectrum. Under purely blues only, it may look nice at first, but some colors will likely fade out and become less vibrant over time due to the fact that color development is often a result of a response to different wavelengths of light. Take away various wavelengths, and they'll stop producing those color pigments. Your fish colors will be bland and ugly as well without that full spectrum. Focus on heavy water changes, lots of manual removal, toss in an algae Blenny, foxface or zebrasoma tang if your tank is big enough, Mexican turbo snails, and an urchin or two and it'll go away eventually. Especially if you stock heavier on corals. Corals will compete with algae for available nutrients

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GimpyFin · 08/02/2016, 07:25 AM

Red can encourage it a little more, but nutrients are the biggest culprit, IMO. What methods have you tried so far for reducing it?

vhuang168 · 08/02/2016, 07:49 AM

What are your nitrate and phosphate levels? What have you done to reduce them?

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oakengineer · 08/02/2016, 05:25 PM

Quote:

Originally Posted by vhuang168

What are your nitrate and phosphate levels? What have you done to reduce them?

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I'm currently using BRO high capacity GFO in a reactor. I've used a couple of different GFOs in the past. Phosfiltrim and two little fishes. I also have a skimmer and a refugium with chaeto. I do 15% water changes every other, or every third week. I also feed very sparingly. 2 flakes in the morning, and a tiny amount of frozen in the evening. Other than doing even more aggressive water changes, or getting rid of my fish altogether, I'm not sure what else I can do from a nutrient standpoint.

My nitrates and phosphates always read zero per my ATI test kits.

Bpb · 08/02/2016, 05:30 PM

Do you mean api test kits? If you have a lot of algae then they'll keep the water fairly well stripped of no3 and po4 to where tests will yield a false negative. How big is your tank and what is your fish load? Most importantly how old is it

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mcgyvr · 08/02/2016, 05:44 PM

If you can get the rock out then a peroxide dip works wonders on GHA

I do a 50/50 mix of hydrogen peroxide and water..
Let rock soak for 15 minutes while you brush what you can off with a toothbrush and then just rinse it and chuck it back in the tank..
good bye GHA..

Can't hurt to try the actinic only treatment..

I have seen neomeris algae disappear from changing the spectrum of light

oakengineer · 08/02/2016, 06:18 PM

Quote:

Originally Posted by Bpb

Do you mean api test kits? If you have a lot of algae then they'll keep the water fairly well stripped of no3 and po4 to where tests will yield a false negative. How big is your tank and what is your fish load? Most importantly how old is it

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Yes, API. I have a 65 gal and a 15 gal sump. The tank has two clownfish and an orchid dottyback in it. The tank is just over 2 years old.

Bpb · 08/02/2016, 06:30 PM

Able to post a pic?

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08/02/2016, 06:48 AM	#1
oakengineer Registered Member Join Date: Jun 2014 Posts: 234	Color of light that prevents algae growth? I've been working on controlling GHA in my reef tank for about 1.5 years. I have tried everything from a chemistry standpoint. (I'm now down to 3 small lightly fed fish) So I think the lighting is kind of the last major thing to try. I have an Current LED light on my reef tank. Right now I'm running full intensity Actinic and White 12 hours a day. I have heard people suggest that I reduce the photo-period, the disadvantage of that approach is that based on when I'm at the house, I won't see the tank on in the evening if I change it. So I'm wondering if I can adjust the type of light to control algae. I think actinic is what the corals need, and I have heard white and read grows algae. So will turning white off, leaving actinic on keep the corals alive and keep algae from growing?

08/02/2016, 07:25 AM	#3
GimpyFin Registered Member Join Date: Mar 2016 Location: Portland, OR Posts: 2,032	Red can encourage it a little more, but nutrients are the biggest culprit, IMO. What methods have you tried so far for reducing it? __________________ Brian Current Tank Info: 110 gallon

08/02/2016, 07:49 AM	#4
vhuang168 Registered Member Join Date: Feb 2015 Location: San Jose, CA Posts: 2,136	What are your nitrate and phosphate levels? What have you done to reduce them? Sent from my iPhone using Tapatalk __________________ Vincent 40g custom AIO --> DSA190Pro

08/02/2016, 05:44 PM	#7
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	If you can get the rock out then a peroxide dip works wonders on GHA I do a 50/50 mix of hydrogen peroxide and water.. Let rock soak for 15 minutes while you brush what you can off with a toothbrush and then just rinse it and chuck it back in the tank.. good bye GHA.. Can't hurt to try the actinic only treatment.. I have seen neomeris algae disappear from changing the spectrum of light __________________ Who me?

08/02/2016, 07:13 AM	#2
Bpb Registered Member Join Date: Oct 2012 Location: Texas Posts: 3,148	Sadly it's not that simple. Hair algae can grow perfectly well in only blue light if water conditions are favorable for it. Algae is present due to a combination of factors including but not limited to tank age (the younger the worse), light levels, light spectrum (yes more red light can tend to grow more algae but it's not a deal breaker), available nutrients, bacterial levels, and presence or absence of herbivores. If any one of those factors of multiple are present, algae can and often does take a foot hold. The current LEDs are pretty low power/low par compared to most more conventional or contemporary reef lighting so I'm not sure I would blame them as the sole culprit. You CAN run a tank on purely blue and actinic light but I don't think it'll work as well as you may hope. Corals can grow under those conditions, especially those typically found in deeper regions, but they'll develop their best pigmentation and health under a more balanced full spectrum. Under purely blues only, it may look nice at first, but some colors will likely fade out and become less vibrant over time due to the fact that color development is often a result of a response to different wavelengths of light. Take away various wavelengths, and they'll stop producing those color pigments. Your fish colors will be bland and ugly as well without that full spectrum. Focus on heavy water changes, lots of manual removal, toss in an algae Blenny, foxface or zebrasoma tang if your tank is big enough, Mexican turbo snails, and an urchin or two and it'll go away eventually. Especially if you stock heavier on corals. Corals will compete with algae for available nutrients Sent from my iPhone using Tapatalk

08/02/2016, 05:30 PM	#6
Bpb Registered Member Join Date: Oct 2012 Location: Texas Posts: 3,148	Do you mean api test kits? If you have a lot of algae then they'll keep the water fairly well stripped of no3 and po4 to where tests will yield a false negative. How big is your tank and what is your fish load? Most importantly how old is it Sent from my iPhone using Tapatalk

08/02/2016, 06:30 PM	#9
Bpb Registered Member Join Date: Oct 2012 Location: Texas Posts: 3,148	Able to post a pic? Sent from my iPhone using Tapatalk