I bought this guy three days ago and I found nothing wrong in the begining.After one day,this one became active and always swam near the water surface.I thought it was caused by low oxygen in water or it had parasites in its gill.So I have used methylene blue to treat it for two days.It is still alive but looks really hard to survive.Its spine always remains a bending shape.I do not know what it is that caused its illness.Please help it,please.











