I haven't posted up here in a while because i have been busy with other things and have not had much time to get into fish all my fish have been fine and doing well until last week, my big mono around 16" won't go after any food I put in the tank, previously he was crashing FD krill and silver sides and now he wont go after food. I think he may be blind for some reason because when i put my hand next to him he doesnt move away until i tap him on the head. Is there anything I can do for him and is this permanent? I am worried because even though he is big he hasnt eaten in over a week I dont know what to do