hi mfkers. i just noticed that my koi has a red swollen mouth. a koi's mouth can extend then goes back. however my koi's mouth looks like its extended but can not go back to its original form. there is nothing stuck inside its mouth, i already checked. also i do not think it is mouth rot. maybe an ulcer? i tried to massage the mouth and put it back to normal, however i noticed that the inside roof of the mouth is also red and swollen. right now i am doing only water changes and adding salt, trying to keep the water as best as possible. please advise!
