Spotfin butterfly sick
I have had my spotfin butterfly for about 3 weeks now. He has been doing fine. I added a sailfin tang yesterday and now my spotting is not eating and laying on his side on the bottom. All of the other fish seem to be fine. I haven't noticed the tang picking on him. Are they compatible? He also looks a little discoloured. I lost several fish about 2 months ago so I had been waiting to add more fish. I dont know what else to do. I have 2 clowns, valentini puffer, spotfin butterfly and purple pseudo. It's a 100 gallon tank. All readings are good. Any help would be appreciated.