This post is based strictly on personal experience. I have dealt with GHA to some degree in pretty much every reef tank I have set up in the last 20 years. These have been set up with live rock, dry rock, and everything in between. I have come to a few realizations that seem to contradict what is commonly thought in the hobby.
It is normally posted that if you have GHA you have excessive nutrients (mainly phosphate and nitrate ), too much or incorrect lighting, and an inefficient CUC. I have come to realize that GHA actually needs very little nutrients and lighting to grow, and even flourish.
It is often said that if you have GHA, you have nutrients. If your test kits are showing 0 nutrients, then they are being consumed and held by the algae. I have had multiple tanks (both setup with live and dead, dry rock) that never showed elevated nutrients from day 1, until the day it was overrun with GHA. So what fed the algae? Phosphates always remained under .05 while nitrates always stayed around 5 from the time the tank was algae free until it was completely infested. Maybe the nutrients were bound in the rock and directly feeding the algae…but I guess that is a whole different issue. Result tells me that controlling nutrients in the water column will not guarantee an algae free tank.
Blackouts or reduced lighting are often suggested to combat algae issues. I always thought so too….until I tore down a mature reef tank to upgrade to something larger at which time I put all of my algae covered rock in a Brute container with nothing but my snails and shrimp. It remained this way for almost two months, doing regular water changes. The only light it received was when the 45W overhead basement lightbulb was flicked on maybe once or twice a day….otherwise the rock sat in the dark. The GHA actually flourished and grew in size with 0 light and low nutrients. Did it feed off itself........was it eating inverts lol??
Another solution to solving GHA issues is to add X number of snails to an already infested tank. The only algae free tanks I have kept (including my current setup) are ones where these snails (along with urchins, algae eating fish, etc.) are present from the very beginning. They will help maintain already shortly cropped algae, but they will not eat or clear mounds of long hair algae (with an exception being the sea hare). I had turbo snails the size of tennis balls in my brute with the live rock…..they didn’t touch the long hair algae strands.
So anybody that has had GHA free tanks which are over a year old, how did you do it? Is it bacterial? Is it filling it with frags early on to cover available rock? Growing coralline to take up space? Removing Co2 which could be feeding the algae (which in turn could also raise PH)? I honestly don’t know how to rid an infested tank of GHA without doing a RIP clean or using coral harming chemicals….which is the point of this thread. I need to hear some success stories lol. No, I do not have an algae issue now on my current 11 month old tank.......but I will at some point....at least that is what past history tells me.
It is normally posted that if you have GHA you have excessive nutrients (mainly phosphate and nitrate ), too much or incorrect lighting, and an inefficient CUC. I have come to realize that GHA actually needs very little nutrients and lighting to grow, and even flourish.
It is often said that if you have GHA, you have nutrients. If your test kits are showing 0 nutrients, then they are being consumed and held by the algae. I have had multiple tanks (both setup with live and dead, dry rock) that never showed elevated nutrients from day 1, until the day it was overrun with GHA. So what fed the algae? Phosphates always remained under .05 while nitrates always stayed around 5 from the time the tank was algae free until it was completely infested. Maybe the nutrients were bound in the rock and directly feeding the algae…but I guess that is a whole different issue. Result tells me that controlling nutrients in the water column will not guarantee an algae free tank.
Blackouts or reduced lighting are often suggested to combat algae issues. I always thought so too….until I tore down a mature reef tank to upgrade to something larger at which time I put all of my algae covered rock in a Brute container with nothing but my snails and shrimp. It remained this way for almost two months, doing regular water changes. The only light it received was when the 45W overhead basement lightbulb was flicked on maybe once or twice a day….otherwise the rock sat in the dark. The GHA actually flourished and grew in size with 0 light and low nutrients. Did it feed off itself........was it eating inverts lol??
Another solution to solving GHA issues is to add X number of snails to an already infested tank. The only algae free tanks I have kept (including my current setup) are ones where these snails (along with urchins, algae eating fish, etc.) are present from the very beginning. They will help maintain already shortly cropped algae, but they will not eat or clear mounds of long hair algae (with an exception being the sea hare). I had turbo snails the size of tennis balls in my brute with the live rock…..they didn’t touch the long hair algae strands.
So anybody that has had GHA free tanks which are over a year old, how did you do it? Is it bacterial? Is it filling it with frags early on to cover available rock? Growing coralline to take up space? Removing Co2 which could be feeding the algae (which in turn could also raise PH)? I honestly don’t know how to rid an infested tank of GHA without doing a RIP clean or using coral harming chemicals….which is the point of this thread. I need to hear some success stories lol. No, I do not have an algae issue now on my current 11 month old tank.......but I will at some point....at least that is what past history tells me.
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