kstyle13;945616 wrote: Looks like pineapple sponge. If you place it in the water does it look like a white fuzzy pineapple? If so it's normal and completely harmless. I have tons. It's a new tank hitchhiker but can also stay present even after all their food is depleated. If you have one there are def. A lot more you haven't found. They are good guys tho to answer your question