I'm starting this thread to document my battle with GHA and hopefully someone down the road will find it and maybe it will help them. I've found there are vast amounts of information and "opinions" about the cause of this nuisance algae and how to solve it.
I've overcome my "shame" in having an ugly algae problem and included my "before" pics below, for posterity.
I welcome opinions, thoughts and friendly debate in this thread. My comments below are purely anecdotal. If you do have an opinion, I ask that you support it either with links, or with your own personal experience. Too many of these threads have people commenting without any support or anecdotal personal experience. I think those comments can lead people down the wrong path.
Some background. I've been keeping reef tanks for about 20 years. Over that time I've had 6 tanks: 10g, 20 long, 34g hex, another 20 long and my current 300g. When I first started, I used tap water filtered through a Brita. No other water conditioner. I had a 250w metal halide hanging on a coat rack above the 20L. That first reef thrived like nothing else. The temp fluctuated between 78 and 85 during the summer and I floated bags of ice to cool it down. I never had any issues with algae of any kind until my current 300g. My tank prior to the 300g was a 20 long. I had that running for 5 years and upgraded it to the 300. Then the GHA reared its head.
Age: Tank is 5 years old but its an iteration of a previous tank. Rock was uncured liverock (told myself I'd never do that again but it looked too nice). I cured it for maybe 3 months in a giant tub with heaters, pumps etc. Some of the rock is from the prior tank.
Here is a pic of the tank December 2014 when it was first setup without any livestock:
3" sand bed on half the tank. other half is bare.
Filtration: Reef Octopus 5000ext. The 114w UV is plumbed inline with skimmer. Entire equipment is in my sig.
Inhabitants:
6" Magnificent Foxface
10yr old b/w Ocellaris
Banded goby
Purple White Wrasse
Royal Gramma
Scarlet Cleaner
Feeding: 2x per day. Rods or flake. maybe 1/2 cube to 1 cube total.
My tank parameters are:
Ph: 7.8-8.1
Alk: 8.5
Ca: 455
Mag: 1320
Nitrate: 0
Phosphate: 0 (highest ever was .02) - Hanna ULR
Temp: 78.5 - 79.5
I have a 114w UV, with slow flow through it ~700gph. I aggressively skim.
I make my water with a 6 stage spectrapure. I use a big blue carbon as well. My water comes out crystal clean and pure.
I started with 6 kessil a360w. Currently have 4 mitras 7. Will update the schedule this evening.
I've probably read 90%+ of the GHA threads on this site and R two R. Most people comment that the poster must have a nutrient problem because the GHA is the evidence of excessive Phosphates. They often state that "the GHA consumes the phosphates before it gets to your test kit". I believed this and it guided my attack on the GHA.
I added GFO, yet the GHA still persisted and my phosphate reading was still 0. I read more posts, of people with similar experiences, and they were advised that the GFO must be getting exhausted extremely fast and that they must still have a phosphate issue. I again believed this guidance and began aggressively changing out my GFO, expense be darned. Yet my GHA still persisted and my corals suffered. I stopped with the GFO.
During this time I also aggressively pursued manual removal via scrubbing and siphoning. I would also scrub and use filter socks to collect the algae that blew around the tank.
The GHA persisted and regrew where I scrubbed.
I've been battling this for 2 years now. I can't tell you how many times I thought about giving up on the 300 and moving back to a 20l or 40b. Its not practical to remove rocks from a 300, scrub and use H2O2.
I began to think more logically about this problem and continued reading more threads. The OVERWHELMING advice is that if you have a GHA issue, you have a nutrient issue and you need to focus on your husbandry.
My wife was a bio-chemistry major, and is a veterinarian, and I talked about this issue with her and about all the various advice. One thing I found extremely difficult to understand was how could the algae possible consume the phosphates before my test kits could detect it? If there is phosphate in the water column and I have a nutrient issue, shouldn't those phosphates be evenly distributed as a "solution"? Its not like the algae is a high powered electro-magnet and the phosphates are pulled to it like metal. I asked my wife about it and she thought there is no way these "theories" could be true. The algae is definitely consuming phosphate, but its not magically pulling all the phosphate out of the water before I could test it.
I again read more threads on this topic and began to see some people state that, just because you have GHA doesn't mean you have a nutrient "problem" and GHA can survive in low nutrient systems with 0 measured phosphates. I discussed this with my wife again. She said while she doesn't know about the specific phosphate needs of GHA, she would assume the Hanna ULR tester is not sensitive enough to measure extremely low amounts of phosphates and there is likely some in the water. I also read some comments suggesting that GHA can almost self-sustain, to a given level, by feeding themselves their own phosphate via tiny amounts of die off.
I've come to believe that the GHA in my tank is "surviving", though not "thriving" in my ultra low nutrient tank through its own release of phosphates due to tiny amounts of die off and the almost undetectable level of phosphates in my water column. I base this opinion off the following:
1. The phosphate level in my tank is at an undetectable level to the Hanna ULR tester, and I do not have a phosphate problem in my water column. I trust this reading.
2. The algae does not and cannot access the phosphate in the water column "instantly" giving me a misleading reading on my tester.
3. When I scrub the rocks, the GHA slowly comes back but seems to reach a maximum growth level. Although its covering most rocks, it does not continue growing and there are patches of rock it does not grow.
4. The GHA is feeding itself with the .0007 level of phosphate in my water column in addition to locally releasing phosphates via die-off and re-consumption.
I'm not sure my plan of attack from here on out. I'm reluctant to add chemicals to my tank, but I fear that might be my only option. Since I definitely do not have a phosphate "issue" with my tank, further attempting to strip phosphates from the water column via GFO will be fruitless.
I must attack the GHA at its source, not through a proxy war with phosphates.
My current working plan is to attack the GHA with an aggressive scrubbing, water change and then dose fluconazole. After about 6 weeks, assuming die off, I will remove the fluconazole and install Bud's Turbo ATS. Hopefully this can out-compete the GHA for what little phosphates are in the water column.
Anyone is free to chime in on this thread with their experiences! I'll keep updating as I try different things to get this under control.
I've overcome my "shame" in having an ugly algae problem and included my "before" pics below, for posterity.
I welcome opinions, thoughts and friendly debate in this thread. My comments below are purely anecdotal. If you do have an opinion, I ask that you support it either with links, or with your own personal experience. Too many of these threads have people commenting without any support or anecdotal personal experience. I think those comments can lead people down the wrong path.
Some background. I've been keeping reef tanks for about 20 years. Over that time I've had 6 tanks: 10g, 20 long, 34g hex, another 20 long and my current 300g. When I first started, I used tap water filtered through a Brita. No other water conditioner. I had a 250w metal halide hanging on a coat rack above the 20L. That first reef thrived like nothing else. The temp fluctuated between 78 and 85 during the summer and I floated bags of ice to cool it down. I never had any issues with algae of any kind until my current 300g. My tank prior to the 300g was a 20 long. I had that running for 5 years and upgraded it to the 300. Then the GHA reared its head.
Age: Tank is 5 years old but its an iteration of a previous tank. Rock was uncured liverock (told myself I'd never do that again but it looked too nice). I cured it for maybe 3 months in a giant tub with heaters, pumps etc. Some of the rock is from the prior tank.
Here is a pic of the tank December 2014 when it was first setup without any livestock:
3" sand bed on half the tank. other half is bare.
Filtration: Reef Octopus 5000ext. The 114w UV is plumbed inline with skimmer. Entire equipment is in my sig.
Inhabitants:
6" Magnificent Foxface
10yr old b/w Ocellaris
Banded goby
Purple White Wrasse
Royal Gramma
Scarlet Cleaner
Feeding: 2x per day. Rods or flake. maybe 1/2 cube to 1 cube total.
My tank parameters are:
Ph: 7.8-8.1
Alk: 8.5
Ca: 455
Mag: 1320
Nitrate: 0
Phosphate: 0 (highest ever was .02) - Hanna ULR
Temp: 78.5 - 79.5
I have a 114w UV, with slow flow through it ~700gph. I aggressively skim.
I make my water with a 6 stage spectrapure. I use a big blue carbon as well. My water comes out crystal clean and pure.
I started with 6 kessil a360w. Currently have 4 mitras 7. Will update the schedule this evening.
I've probably read 90%+ of the GHA threads on this site and R two R. Most people comment that the poster must have a nutrient problem because the GHA is the evidence of excessive Phosphates. They often state that "the GHA consumes the phosphates before it gets to your test kit". I believed this and it guided my attack on the GHA.
I added GFO, yet the GHA still persisted and my phosphate reading was still 0. I read more posts, of people with similar experiences, and they were advised that the GFO must be getting exhausted extremely fast and that they must still have a phosphate issue. I again believed this guidance and began aggressively changing out my GFO, expense be darned. Yet my GHA still persisted and my corals suffered. I stopped with the GFO.
During this time I also aggressively pursued manual removal via scrubbing and siphoning. I would also scrub and use filter socks to collect the algae that blew around the tank.
The GHA persisted and regrew where I scrubbed.
I've been battling this for 2 years now. I can't tell you how many times I thought about giving up on the 300 and moving back to a 20l or 40b. Its not practical to remove rocks from a 300, scrub and use H2O2.
I began to think more logically about this problem and continued reading more threads. The OVERWHELMING advice is that if you have a GHA issue, you have a nutrient issue and you need to focus on your husbandry.
My wife was a bio-chemistry major, and is a veterinarian, and I talked about this issue with her and about all the various advice. One thing I found extremely difficult to understand was how could the algae possible consume the phosphates before my test kits could detect it? If there is phosphate in the water column and I have a nutrient issue, shouldn't those phosphates be evenly distributed as a "solution"? Its not like the algae is a high powered electro-magnet and the phosphates are pulled to it like metal. I asked my wife about it and she thought there is no way these "theories" could be true. The algae is definitely consuming phosphate, but its not magically pulling all the phosphate out of the water before I could test it.
I again read more threads on this topic and began to see some people state that, just because you have GHA doesn't mean you have a nutrient "problem" and GHA can survive in low nutrient systems with 0 measured phosphates. I discussed this with my wife again. She said while she doesn't know about the specific phosphate needs of GHA, she would assume the Hanna ULR tester is not sensitive enough to measure extremely low amounts of phosphates and there is likely some in the water. I also read some comments suggesting that GHA can almost self-sustain, to a given level, by feeding themselves their own phosphate via tiny amounts of die off.
I've come to believe that the GHA in my tank is "surviving", though not "thriving" in my ultra low nutrient tank through its own release of phosphates due to tiny amounts of die off and the almost undetectable level of phosphates in my water column. I base this opinion off the following:
1. The phosphate level in my tank is at an undetectable level to the Hanna ULR tester, and I do not have a phosphate problem in my water column. I trust this reading.
2. The algae does not and cannot access the phosphate in the water column "instantly" giving me a misleading reading on my tester.
3. When I scrub the rocks, the GHA slowly comes back but seems to reach a maximum growth level. Although its covering most rocks, it does not continue growing and there are patches of rock it does not grow.
4. The GHA is feeding itself with the .0007 level of phosphate in my water column in addition to locally releasing phosphates via die-off and re-consumption.
I'm not sure my plan of attack from here on out. I'm reluctant to add chemicals to my tank, but I fear that might be my only option. Since I definitely do not have a phosphate "issue" with my tank, further attempting to strip phosphates from the water column via GFO will be fruitless.
I must attack the GHA at its source, not through a proxy war with phosphates.
My current working plan is to attack the GHA with an aggressive scrubbing, water change and then dose fluconazole. After about 6 weeks, assuming die off, I will remove the fluconazole and install Bud's Turbo ATS. Hopefully this can out-compete the GHA for what little phosphates are in the water column.
Anyone is free to chime in on this thread with their experiences! I'll keep updating as I try different things to get this under control.
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