Unknown problem with Yellow and Hippo Tangs


Premium Member
I honestly don't know what happened to my healthiest and fattest Yellow and Hippo tangs. First off, my 90G is a reef tank with nearly perfect specs - RO + double DI water, minimal temp fluctuations; excluding one coral (AEWFS) everything is thriving and growing. Feeding regimen is a concoction of prepared foods including fish caviar (once a week), CP, assorted marine meats plus nori for tangs. Both Hippo and YT were in my tank for almost a 1.5 now and grew from about an inch for Hippo and 2" for YT to about 5 inches (both).

Recently I bought CB Butterfly and bought some live brine shrimp to get him started. For three days everyone looked fine. On the forth day Hippo stopped eating and before the lights out I noticed that he had a pinched stomach at around its anal fin. The next morning he wouldn't come out from his hiding place. At the end of the 5th day YT developed the same exact problem.

Today both breathe heavily and remain in one spot. Both tried catching some food but can't swallow it. The rest of the fish: mated pair of clowns, pseudochromis, 2 blue chromises, six-line wrasse and CBB are doing great.

I always “wash” live brine shrimp in a bit of tank's water then strain them into the feeding cup to avoid adding LFS water into the tank.

Is there anything I can do to help those two and what could possibly cause this problem? P.S. YT tore a nori sheet apart a night before it developed that problem. Could it be internal parasites? I’d hate to see them perish.

Thanks, Art.


My guess is it could be stress. 90G is kind of small for those 2 tangs. They were probably alright before, but adding the butterfly could have set them off.

Good Luck!!!