gill disease?

[chrissssssssssy]

I moved my boyfriend's two tanks to my new house a few weeks ago (He's in the army, and I'm taking care of them for him while he's overseas...doing my best, but this is his hobby, not mine). Four days ago my biocube sprang a leak (probably a result of moving), so I was forced to move my 2 ocellaris into a quarantine tank that I had never set up. The biocube was 14g and in one year, I never had any problems with the setup. The quarantine is only 9g, but I assumed that if I did enough water changes, they would be okay until my boyfriend gets back next month. Apparently this is not true.

The dominant fish of the pair always eats straight from my hand, so when she didn't make a beeline for breakfast this morning, I knew something was wrong. She was in her hairy mushroom which they host panting heavily. Long story short, I did about a 40% water change, she's still panting, and her gills look frayed. Other than that, her coloration is fine, her swimming isn't erratic, just a little lethargic.

I suppose my question is, should I use the antibiotics I had on hand? I'm going to have to treat the whole tank though because they're already in my quarantine. Right now it's two ocellaris, their hairy mushroom, and a turbo. The antibiotics I have are Mardel Maracyn-Two.

Also, I should say that I tested all water parameters with my kit, but I think it's expired and giving me inaccurate results. Salinity is 1.020.