u/Far-Leopard-9326

I’ve been busy the past day or 2 so I haven’t really inspected my tanks. Last night I noticed this tumor looking growth on one of my males and was wondering if any of you can identify what’s wrong and what I should do!!?? Or possibly what could have caused this if everything parameter wise is fine, he is acting fine, and nothing has been changed. He is in a 10 gal by himself, although I did find a ramshorn snail a few weeks ago in here from moving some elodea and he hitched a ride.