He was the one I was talking about awhile ago if I should pop his inverted bubble mouth. I remember you told me not to pop it (I never did it myself) and to focus on water quality which I did. He has had an inverted "bubble" mouth for close to a year. The two clowns hosting him are decently hard on him (nuzzling up on him with force), but he is also a relatively large haddoni.
A few days ago, I put in a hydro PH to see if extra flow might help (thought there may have been a dead spot), left it on for 3 hours and I believe he started expelling a ton of zoo (though it is not for sure - it was stringy and light brownish). I then fed him (I know now I shouldn't have) two small pieces of shrimp to help get protein after seeing him expell whatever he did and he ate them. The next day he perked up and looked great. This morning he also look good (the bubble has never been smaller then it was this morning). I saw the hole while moving a small rock and I could see some of his tissue hanging on being blown from the current where the hole is. I have had him for many many years, and this inverted "bubble" mouth problem only happened once I moved him to his new tank and it has never gone away since - even when he eats (he was under 150 watt mh and now he has been under dual 400 watt metal halides).