One of my Angelfish has unfortunately got what seems to be an internal parasite. It has been passing white fluid and hasn't eaten for 6 days now. I've raised the water temp to 84f (29c) and have been treating the water also for 5 days with waterlife sterazin. He isn't swimming differently but always looks lethargic ever since. The white fluid seems to have stopped passing through though. Any suggestions as to what else I could do? I'm becoming quite concerned now.