I have had my dogface puffa for 4 months now and he has got very poorly. He is covered in white powder like all over his body and is staying a dark grey colour rather than his bright white colour. He just wants to hide and is not eating much either. I have set up a qt for the little one but he aint looking good. He is normally housed in a 480l tank with 2 rena xp3 filters with uv, aquamedic 1000 turbofloater skimmer with ozone. Can any one help !!!!