my blue crowntail has edveloped something very bad.
yesterday afternoon i changed his water and he looked fine. i also checked him this morning and he even played with my finger. when i came home tonight, i saw him very sick. he dveloped some sort of fungus-like stuff on his belly side, just below his gills. he looks like he's having a hard time and i feel very bad for him. the white stuff looks like as if it has eaten some parts of his body and exposed it. i don't know whter this is body rot or advanced state of fungus. what's bothering me is how he developed it in very little time. he lives in a 2.5 gal tank alone. i do partial water changes religiously also. what i did for now was to replace the water again and pout some methyline blue and alittle salt in the replacement water. please tell me waht to do, thanks!