So today I did my normal water change of about 20gallons and went to work for about seven hours now that I'm home his massive kok has lost at least an inch and looks almost loose and soft. He's in a 75 running a fluval 405 and an ac110, tank is well established and has been for about a year. My test kit is old so I won't be able to get an accurate reading till tomorrow but the tank has never had an issue before regarding water quality. He was almost full grown when I got him with the only noticeable growth being in his kok. Now it's smaller then I have ever seen. Any ideas?