Hi, I have kept a Bolivian ram for the past 2 months and as of the last couple of days he looks really ill. He has gone a deathly grey colour and this morning he was lying on the gravel leaning against the bridge on the bottom. His eyes are almost lifeless and he is hardly moving. I have had a lot of bother with water quality lately and been having it checked weekly, However, yesterday I got an all clear. He does not seem to be eating anymore. the tank I have is a 64 Litre tank with approx 18 fish mainly neons and tetras, He doesn't seem to have any lumps or sores on him and it is a complete mystery. Any advice would be greatly appreciated. Thanks in advance.