High Ammonia in QT = not good

[saltyrockbox]

I put my coral beauty into QT because it developed one cloudy eye.
The QT tank is a 10g with no biological filter. I dosed the little tank with AP Erythromycin (which would've kill any biological filtration...)

I went through a full box of Erythromycin but he actually got worse. his tail developed a little whole in it.

One of the problems was I couldn't keep the ammonia down. I did a 50% water change every other day like the box said and still I had 2ppm ammonia.

How do you use antibiotics and keep the tank water chemistry clean and free of ammonia?

Was that medication correct for one cloudy and slightly popping eye?