Cloudy eye is a bacteria to a parasite depending on WHERE you read about it at.. I have this in a severum and Have treated hiim with Melafix AND PrimeaFix for 7 days.. Seems to disappear at the end of the 7 days..
YOU dont' say How your water tested, Ammonia, nitrite and NITRATE readings.. Or how big your tank is..
WEEKLY tank maintainence, vacuum the gravel, water changed/filter cleaning are very important when you have Oscars.. What you feed them and most of the time, they filter it through their gills making a mess in the process.. I always had others in with mine that ate what came out of his gills.. My midas loved to eat under him.. amazing as that sounds.. NOTHING touched the gravel with the Midas in the tank.. The sore on the Oscars side wil benifit from the melafix and PRIMEAFIX too.. use them together and in 7 days, you should see improvements in both....
ON the cloudy tank, how much water do you remove at one time?? seems that you might be taking out to much and that has has your bio trying to restart its self.. White cloudy is a bacteria bloom.. Some ppl put another filter on the tank and that seems to clear it up faster.. Water changes should be done at not over 30% of your tank water volume.. IF you change out more, like 50% and more, you risk disrupting your bio and that causes a white bacteria bloom.. Most clear up in a few days but I dont' recall one lasting a month.. Seems something else is causing this to not settle out.. To much current from power heads OR other strong currents in the tank.. ONLY you know how your tank is set-up, I am just guessing here on possibilities

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