Yellowfin Damsel

[mjwz06]

Need diagnosis and treatment advice for my first sick fish. Here's what I have:

72g w/ 15g sump
90 lbs LR
protein skimmer
and I'm running carbon passively

I have standard CUC of snails, hermits
2 peppermint shrimp
1 perc clown
yellow damsel
blue devil damsel
blue yellowtail damsel
frogspawn and mushroom corals

The tank has been running for about a month, but the LR was already cycled, and water parameters have been steady:

SG 1.024
pH 8.2
ammonia 0
nitrite 0
nitrate <5
phosphate 0
Ca 360
dKH 9

I picked up the damsels about 2 weeks ago from a LFS, and they've been doing well up until today. I'm feeding once/day - either frozen mysis or freeze dried brine shrimp. All fish have been eating healthily and show no signs of stress.

So today I notice that my yellowtail damsel swimming near the surface, in the corner. And he's keeled over to the side slightly. No visible ich spots or any torn fins. So I try feeding, and he doesn't care to eat.

Any possible diagnosis? I just bought a 10g to set up a QT, but I'm not really sure how to best treat him. Any suggestions would be appreciated.

Thanks in advance!

Mike

 

[mjwz06]

Here's a pic of him swimming...