I wouldn't really recommend Erythromycin as it contains anti-biotics. I think its best to just use mild medications like General Cure, Melafix, Pimafix or aquarium salt since you're just buying fishes.Celestialpearl said:You could, but I wouldn't personally. I'd recommend starting with something less potent if you want to medicate. I do medicate on quarantine and I find E.M. Mycin, General Cure, and Methylene blue or Ich X work well in combination. Just erythromycin and general cure, alone or together work well too.