Losing acro colonies!


New member
Don't know what's going on with my tank,everything has been fine and stable.i had a lot of algae growing in my overflow and decided to clean it out,that's when I think my trouble started.about half of my acro colonies started to turn white from the bottom up,gone in a day or two.did a large water change and checked all of my parameters ,everything seems fine.just before I did the cleanup my phos was at .43. I changed out my gfo/carbon and last read .09
Sal .025 alk alk 10.5, still losing colonies while others seem ok..ideas?
Cal is a little high at 490
One other thing ,,,I did use red slime remover about a week before all of this started...all of my other livestock are fine..just the acros.
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2018 FMAS President
Often the ingredient in red slime remover is an antibiotic, usually erythromycin. Antibiotics KILL bacteria. IMO these antibiotics do more harm than good. :(

IME acros and other sps will bleach when stressed. When you see bleaching, it is because they are expelling the bacteria from their bodies. In the wild some of the corals will retake the bacteria back into their tissues and recover. Your bleaching was probably caused by the high phosphates (stress); then topped off with an antibiotic (more stress)

Run carbon to remove the rest of the antibiotic
ad bacteria booster like Fritz
Frag colonies that show signs of RTN or bleaching


New member
Sorry to hear. I sometimes will get couple corals to rtn out of the blue. Especially my orange and green birdsnest. But that is usually welcomed. ( :

Po4 of .4 is very high as you know for SPS. Im guessing that was one of the factors

As Dr T said. Run some carbon and get the params in good shape


New member
amazing how little it takes to kill off coral...lucky the oceans are stable
working on stabilization...and getting some new frags for replacement