Get him off the layer feed, too much calcium.Yes, he was in a pen alone and these are what I gathered when I cleaned it up before going to bed. He has been eating a 16% layer feed and once a day I add fermented (wet) layer feed with some oatmeal in it. He also get some bsf larvae. He's drinking a lot of water. I just realized the electrolyte makes the water yellow. I'm going to give clear water tomorrow and see if that is it.
Electrolytes should not be given non-stop, just once a week if they are really necessary.