renisel
02/27/2009, 01:51 PM
The corals in my SPS tank were thriving up until a couple months ago. At that point, some started to fade, and polyp extension began to decrease. Then I started seeing STN on one coral after another--mostly acropora and to a lesser extent montiporas. Birdsnest, stylos, pocilloporas and hydnophora show little to no effects, while my psammocora has browned and receded slightly, but not died off like the acros and montis.
It's been baffling me, since all of my water parameters seemed to be right on (0-3 ppm NO3, 0 ppm PO4, 425 ppm Ca, 175 ppm CO3, 1300 ppm Mg, sg 1.026) and I have not been able to find any evidence of harmful parasites. Then, the other day, I decided to try testing the alk with a Seachem test kit instead of the Lamotte kit I usually use, and it showed the alkalinity to be around 125 ppm. I usually don't test pH because I figure it should be fine so long as the alkalinity is good, but it turned out to be peaking at around 7.8-7.9. So I'm figuring my Lamotte kit went bad or got contaminated somewhere along the way and has been giving me bad readings--but 125 ppm CO3 and a pH of 7.8 shouldn't be disastrous, should it?
I have also seen a green hair algae outbreak progress as these problems have developed. As the NO3 and PO4 levels have always been minimal, I figured that the algae was sucking up the excess nutrients before they could cause a problem, and have thus written that off as a potential cause of my main problem. Should I be more concerned about it than I am?
Since finding out that my alkalinity levels appeared to be low, I have increased my carbonate supplement to gradually bring the alkalinity back up and the pH has been staying in the 8.1-8.3 range for the last couple days. I haven't yet seen any noticeable change in polyp extension or coloration. If it was a pH/alk problem, how long should it take before I start to see some recovery? And is there anything else I should look for as possible causes of the problem? Thanks.
It's been baffling me, since all of my water parameters seemed to be right on (0-3 ppm NO3, 0 ppm PO4, 425 ppm Ca, 175 ppm CO3, 1300 ppm Mg, sg 1.026) and I have not been able to find any evidence of harmful parasites. Then, the other day, I decided to try testing the alk with a Seachem test kit instead of the Lamotte kit I usually use, and it showed the alkalinity to be around 125 ppm. I usually don't test pH because I figure it should be fine so long as the alkalinity is good, but it turned out to be peaking at around 7.8-7.9. So I'm figuring my Lamotte kit went bad or got contaminated somewhere along the way and has been giving me bad readings--but 125 ppm CO3 and a pH of 7.8 shouldn't be disastrous, should it?
I have also seen a green hair algae outbreak progress as these problems have developed. As the NO3 and PO4 levels have always been minimal, I figured that the algae was sucking up the excess nutrients before they could cause a problem, and have thus written that off as a potential cause of my main problem. Should I be more concerned about it than I am?
Since finding out that my alkalinity levels appeared to be low, I have increased my carbonate supplement to gradually bring the alkalinity back up and the pH has been staying in the 8.1-8.3 range for the last couple days. I haven't yet seen any noticeable change in polyp extension or coloration. If it was a pH/alk problem, how long should it take before I start to see some recovery? And is there anything else I should look for as possible causes of the problem? Thanks.