Dogface Puffer disease??

[monza]

With out a picture I'm just guessing but it could be a common ailment known as lymphocystis. It's an infection that sort of looks like cauliflower and happens with poor water quality usually on newly shipped fish. With quality water it can clear itself up so keep doing water changes. It could also be cotton mouth and you'd have to most likely treat it but I don't know much about it. Do some searches see if you can post some pics.

Good luck.

Dave