This is a post from aquanero hope he doesnt mind but i saw this post a figured it would help. He is very knowledgable so I would trist his advice.
Pop eye is a symptom of an underlying bacterial infection. I've had luck in the past with Tetracycline. It will damage your bio filteration so it's best to treat in a QT tank. Plenty of clean water (water changes and treat as directed) treated with the meds should clear it up. I've seen fish loose vision and in some sever cases the eye. Epsome salt also heps releave the fluid build up behind the eye. If done as a bath seperate form the antibiotic in the hospital tank. This is all very stressfull on the fish so you might want to start with one or the other as opposed to slamming it all at once. Post a pic if you can. GL
Alright I ended up going home for lunch and did a 50% water change. Added more salt and am looking into getting some tetracycline. I might have to do the whole Epsome salt route as his eye needs some relief on the swelling. I did manage to take a quick pick of him to show how much worse it has gotten.
Oh and as far as parameters it was showing the start of turning pink for NO3. Everything else seemed like it always does.
Well the worst happened... I ended up being stuck in my bed for two days straight and both arms swollen to the point I was losing feeling in my hands. I went down to where I keep my tanks as soon as I could and there he was floating at the top.... I only have two females now and the whole reason I got them was to breed.
sorry for your loss, i was gutted when one of mine managed to get ontop of the glass cover (came out through the filter gap) even worse was i had my tank lights on so it was partially cooked
How did you sex yours btw? I originally started with 6 and now have 4 , largest is around 6 1/2inch smallest is about 4 inch