My rosy barb is not too rosy for this days. he's kind of black from the middle to the top of his body, his not like that usually. Almost he is swimming in a strange way, and his not feeding as the others. ??? ???Is he sick??????? please help me with this i don't know what to do with him. ??? ??? My ammonia and nitrates level are OK, I've been feeding them with tetra color, with vegetables and with spirulina. Do i have to take him away from the others??