I recently moved my oscar and tankmates into his new 120 gallon tank but a couple of days before the move he developed a bit of cloudy eye,i put it down to stress of being cramped in tne 40 gallon.Over the course of the last 2 weeks it has gotten worse and has spread to my 2 firemouths,i have just completed a course of myxazin but it has had no effect if anything it is worse.Water quality is perfect,feeding well and still active,there is ever so slight fin fraying.i just dont know where to go next with this,any help greatly apreciatted.

That dont look so great iv never seen it before but I wouldn't worry to much some body hear will know what to do so hang on.

If it is what I think it is (bubble eye) than there really isn't a cure At least I have never heard of a good one. Maybe someone else will come along with a cure but I have never run into one. Sorry wish I could be more help

When kept in tanks Oscars may damage the outer layer of their eyes on their surroundings.
These wounds will heal, given time, pristine waterconditions and a healthy varied diet if they're superficial .

But as you say the other fish are getting infected too, so it must be something different.
Can we get the actual testresults for ammonia, nitrites, nitrates and pH?

can you brief us what have you done in moving them into the new tank?
the fishes had acquired the problem at the old crowded tank...and the
new tank could have ease-out the problem if done properly....

pop-eye is the build-up of liquid inside the eyes and most of the time
can be cured by applying correct dosage of epsom salt. however, the needs
for pristine water is needed, otherwise, treatment will be useless.

OMG this is serious my first 2 Oscar die from that about 10 years ago at about 6-7 inches, from what I know it can be poor water condition + low water temperature. changing water condition does not help that time, should get some medication for it, it did not work for mine last time

thanks for all the advice.I cycled the new extra filter on my previous tank for about 5 weeks before the move so water conditions were not an issue even with it being overstocked as i had filtration for almost 250 gallons on a 40g,thats what so confusing.my current water readings are ammonia 0,nitrites 0,nitrates 40(my tap water has high nitrates anyway 30ppm and i havent done a water change for 7 days becaue i didnt want to stress fish while medicating)i was wondering if it could be flukes maybe im clutching at straws now?

wow 40ppm of nitrate, by what I know high nitrate isn't good for fish, and it can cos green water, all I can think of is getting some plant or let the algae grow which would cut down on the nitrate, but isn't so effective, but the least can be done, unless you can get a refugium tank. how about your water temperature cool hot?
also minimal water change would not stress your fish. I have overstocked tank too Oscar is fish that poop a lots I do water change all the time in a 4 feet tank about 50 gal, 2 bucket about 50 liter least each 1 or 2 days.

I was too stubborn before about how much fish I should have in 1 tank now I can only try to cope up with the water quality super over stocked tank 8 Oscar, 4 Giant gourami, 10 climbing perch or called climbing gourami. also 1 large pleco. eventually giant gourami just don't get a long well now down to 2 giant gourami, and 1 Oscar is move to new tank alone because growth rate are too slow or kind of sick not sure.

and good luck on the treatment hope you can share the experience here when the fish get well

i keep the tank at 82 degrees,gona do a water change tonight and see what its like tommorow.the firemouths one eye looks terrible now like its rotted out,ill try to get a picture but he is very inactive now hiding all the time

i was told that epsom salts help release fluids in the case of pop eye, just add 1tablespoon/5 gal water. an antibiotic could help heal the infection....