I bought a tiger oscar 5-6 months ago and it has been doing well, but up until the last few days, agter i cleaned the water it has stopped eating and would be really picky with the food, it would lay down at the bottom of the tank not moving its fins and i noticed a scrape on the side of her belly that has continued to grow bigger, ive spoken to the place where i brought her from, they gave me medicine for fungus. And said im just not cleaning the water properly. Its my first fish and i dont want to lose her. The other oscar is doing fine but she isnt, the scraped part became white
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