Trenton Henderson
Active Member
Hey everyone!
I have had some strange things occurring with my three acropora frags that I got a month and a half ago.
For quite some time, everything had been looking great. Two out of the three (green slimer and WWC yellow tip austera) were growing (either encrusting or growing out) and coloring up. The third, a paletta pink tip, began to base out and then began getting pale, showing filaments, and then RTN happened. I moved the frag down from 300-315 PAR to 250ish PAR while this was happening and the tissue, though bleached remains in tact on the underside of the coral. There is even a bit of non-bleached tissue on one side.
A few weeks later, the tip of my green slimer looked like its tip got scraped off (with some skeleton too), but it seems to be healing alright. No sign of bleaching there. Finally, as of the last couple days, the yellow tip austera has lost some color near the tip and some tissue as well. I see some signs of mesenterial filaments on it as well, despite the base having full polyp extension and looking healthier than the tip. This coral receives 275-300 PAR.
What is very strange to me is that everything has remained quite stable:
Salinity: 1.026 sg
pH: 7.9-8.0
Alk: 8.0 dKH
Mg: 1290-1350 ppm
Ca: 420 ppm
Nitrate: 4-7 ppm
Phosphate: 0.06-0.11 ppm
The only fluctuations that have happened were that the alkalinity dipped to 7.4 or 7.5 dKH because I had a growth spurt of coralline and some other corals, so I turned up the doser. It did fluctuate between 7.6 and 8.0 dKH for a couple days while I stabilized it. I recently raised Mg back into the 1300's. Phosphate went up quickly for some reason, but is on its way back down. Today it sits at 0.08 ppm. Nitrate floats around a bit and I have to dose it occasionally. Also, I do a 20% water change every two weeks and use Red Sea Blue Bucket. I also feed aminos a couple times a week (Red Sea and Brightwell Restor).
All acros appear to be pest-free, and numbers haven't fluctuated much. The only thing I can think of is that the iodine concentration in the tank may be low. I have a slow burn montipora and it was nearly dead (had only a few bits of tissue left). I dosed a little bit of Brightwell Iodion to get it back to about 0.05 ppm, and within a month, it had completely healed and the number of polyps had doubled. Could this be the issue? I just ordered a Red Sea iodine test kit to try and get an idea of whether its bottomed out or not. I don't like dosing the stuff without knowing my level.
Any other thoughts are greatly appreciated!
I have had some strange things occurring with my three acropora frags that I got a month and a half ago.
For quite some time, everything had been looking great. Two out of the three (green slimer and WWC yellow tip austera) were growing (either encrusting or growing out) and coloring up. The third, a paletta pink tip, began to base out and then began getting pale, showing filaments, and then RTN happened. I moved the frag down from 300-315 PAR to 250ish PAR while this was happening and the tissue, though bleached remains in tact on the underside of the coral. There is even a bit of non-bleached tissue on one side.
A few weeks later, the tip of my green slimer looked like its tip got scraped off (with some skeleton too), but it seems to be healing alright. No sign of bleaching there. Finally, as of the last couple days, the yellow tip austera has lost some color near the tip and some tissue as well. I see some signs of mesenterial filaments on it as well, despite the base having full polyp extension and looking healthier than the tip. This coral receives 275-300 PAR.
What is very strange to me is that everything has remained quite stable:
Salinity: 1.026 sg
pH: 7.9-8.0
Alk: 8.0 dKH
Mg: 1290-1350 ppm
Ca: 420 ppm
Nitrate: 4-7 ppm
Phosphate: 0.06-0.11 ppm
The only fluctuations that have happened were that the alkalinity dipped to 7.4 or 7.5 dKH because I had a growth spurt of coralline and some other corals, so I turned up the doser. It did fluctuate between 7.6 and 8.0 dKH for a couple days while I stabilized it. I recently raised Mg back into the 1300's. Phosphate went up quickly for some reason, but is on its way back down. Today it sits at 0.08 ppm. Nitrate floats around a bit and I have to dose it occasionally. Also, I do a 20% water change every two weeks and use Red Sea Blue Bucket. I also feed aminos a couple times a week (Red Sea and Brightwell Restor).
All acros appear to be pest-free, and numbers haven't fluctuated much. The only thing I can think of is that the iodine concentration in the tank may be low. I have a slow burn montipora and it was nearly dead (had only a few bits of tissue left). I dosed a little bit of Brightwell Iodion to get it back to about 0.05 ppm, and within a month, it had completely healed and the number of polyps had doubled. Could this be the issue? I just ordered a Red Sea iodine test kit to try and get an idea of whether its bottomed out or not. I don't like dosing the stuff without knowing my level.
Any other thoughts are greatly appreciated!
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