Hello, I got a new blue diamond flowerhorn about a month ago and just about three days ago he stopped eating and is just sitting at the back of the tank with a slightly swollen belly, white on the edge of his fins and his kok shrunk significantly. He is in a 75 gallon at 78 degrees with 0ppm ammonia and 7.8ph. Here is some photos, if you have any idea what's wrong please let me know and how to treat him!