All of a sudden one day I looked in my divided 3 way tank and one of my fish (a crowntail) has some white goopy stuff hanging off his tail. It looks like what used to build up on my Squidward house ornament in the other divider but I don't see any of the goopy stuff in his divider, just his tail. Granted I'm due for a water change and should have done it Weds but I'm doing one tonight. It looked like a little bit of it knocked off when i gently scraped it with the fishnet before he noticed it and took off. Should it be something to be worried about?