i bought a tiger oscar last night and he is in my tank now, all last night and today he was fine i got home at 5 and he is sitting up in the corner and wont move at all and his scales are peeling off like crazy he looks really white have no idea whats going on. I have a 55 gallon with 3 gold gouramis another tiger oscar a pleco and 2 rapael catfish and a green terror. I did water test and these are the results
nitrate is 20 ppm
nitrite is 0 ppm
hardness is 75
alkalinity is 40
ph is 7.2
i am setting up a emergency tank and adding melafix to it:(

we will try and help as possible. Firstly, we have to address tank size. 55 gallons is really only big enough for one Oscar. How big are all your fish? Are all the other fish behaving normally? You didn't give us the ammonia reading.

If I was you, I would take the fish straight back to the shop. Tell him that the rest of your fish are perfectly okay, there is a chance the fish had something already. Also take a sample of your water so that you can prove that has nothing to do with the fishes problem. Just doublecheck your water and make sure it's okay, if it isn't okay, they are within their rights to refuse to do anything about it

i currently dont have an ammonia test kit but im going to get one tho.

green terror about 3 - 3 1/2 in
1st tiger oscar about 4 in
3 gold gouramis all 3 1/2 in
Common Pleco about 5-6 in
rapheael catfish are 2 1/2 in

and the tiger oscar that is sick is about 2 in
thank u he is in a emergency tank right now and he is swimming around a bit but his scales look bad what reason do u think his scales are flaking for
thanks for all your help Billy