I have a 100 gallon reef tank that appears to be crashing but I cannot figure out why. All water parameters look good. The tank is well established.
What appear to be brown algae or diatoms started growing on the sand bottom. I don't have a test kit for silicates. The LaMotte Nitrate test showed between 1-5ppm no3. I tried a 20% water change using Red Sea salt and RO/DI water. More brown algae continued to grow on the sand.
I tried a product called AZ-NO3 (absolute zero nitrate). Nitrates did come down to zero within a week. Phosphates were also zero. But the polyps on some corals started to stay shut for days. I also noticed the red star which I had had for 6 years, coming out during the day and half the length of his legs were missing. I tested again for Nitrates and it and the rest of the water parameters were good.
All the fish seem fine, a yellow tang, hippo tang, two perculas and some green chomis.
I do not see any pods or other bethnic life in the sand or on the rocks anymore, even coming out and checking with a flashlight at night.
The water has a brownish hue and 100 pounds of live rock seems to becoming covered in a layer of detritus. I can "blow" it off with a syringe and it reappears in a couple days. The foam fractionator is pulling a lot gunk. I've stopped feeding the fish for a few days.
I tried another 20% water change and while there is some improvement, the coral polyps are still not fully extending. Only about half come out at all.
My only two guesses at this point are that the AZ-NO3 caused the problem or something died and released a poison I can't test for, but I dont' know what the something might be since I have never had any sea slugs or inverts that I'm aware of that release poisons when they die.
I'm totally stumped about the cause, or what the cure should be. I'm thinking of a 50% water change and sucking out half the sand bed when I do. I'm afraid of doing nothing and incremental small water changes don't seem to be helping fast enough to save what's left of the corals.
This reef has been up and running successfully for over ten years so I am totally stumped why it went south so quickly. Any help would be appreciated. I don't know how long the corals can survive this way.
What appear to be brown algae or diatoms started growing on the sand bottom. I don't have a test kit for silicates. The LaMotte Nitrate test showed between 1-5ppm no3. I tried a 20% water change using Red Sea salt and RO/DI water. More brown algae continued to grow on the sand.
I tried a product called AZ-NO3 (absolute zero nitrate). Nitrates did come down to zero within a week. Phosphates were also zero. But the polyps on some corals started to stay shut for days. I also noticed the red star which I had had for 6 years, coming out during the day and half the length of his legs were missing. I tested again for Nitrates and it and the rest of the water parameters were good.
All the fish seem fine, a yellow tang, hippo tang, two perculas and some green chomis.
I do not see any pods or other bethnic life in the sand or on the rocks anymore, even coming out and checking with a flashlight at night.
The water has a brownish hue and 100 pounds of live rock seems to becoming covered in a layer of detritus. I can "blow" it off with a syringe and it reappears in a couple days. The foam fractionator is pulling a lot gunk. I've stopped feeding the fish for a few days.
I tried another 20% water change and while there is some improvement, the coral polyps are still not fully extending. Only about half come out at all.
My only two guesses at this point are that the AZ-NO3 caused the problem or something died and released a poison I can't test for, but I dont' know what the something might be since I have never had any sea slugs or inverts that I'm aware of that release poisons when they die.
I'm totally stumped about the cause, or what the cure should be. I'm thinking of a 50% water change and sucking out half the sand bed when I do. I'm afraid of doing nothing and incremental small water changes don't seem to be helping fast enough to save what's left of the corals.
This reef has been up and running successfully for over ten years so I am totally stumped why it went south so quickly. Any help would be appreciated. I don't know how long the corals can survive this way.
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