I see. If I get a medication to treat his bacterial problems, will it also kill the bacterial filter (good bacteria) that I "patiently" waited to establish. I was told by a storekeeper to buy the Tetra product "Anti-bacteria medicated sticks". It is a food to feed to him for 10 days. Any thoughts on this stuff? Any products you can recommend if treating the water is the best way to help this fish? Thanks for all your kind and insightful advice.