My water is testing fine and all the other fish are looking fine but he is pale yellow with black spots and looks like he is rotting. I have API fungal cure and API all cure - which one should I use? I don't have a QT tank so should I medicate the whole tank?
Yes, DGD will only infect other DGs, can you post a picture? It would really help. Also, some good things to post right off the bat are your water params. You should also take some time and fill out your profile. (And to FishLore!)