Hi everyone, so I had my small 2-inch fantail in a 30 gallon tank with another fantail that was about 3 and 1/2 inches since August. There hadn't been too much of a problem before but a few days ago I noticed my small fish's tail looked chewed on. I removed the ornament that was in there (as advised by a member on here) and left him overnight. Thursday when I came home he was stuck to the filter intake. I went to remove him with a net but he swam away so I moved him into my 10 gallon tank that had just been cycled (was planning on re-stocking this weekend). His tail had been chewed ALOT and he was very scared. I fed him a little and he ate a bit but he was hiding most of the night. Since then he has been eating a good bit more, he is defecating, and he doesn't seem as scared. Yesterday, however, I noticed a little bit of whitish fluffy stuff on his tail where it had been bitten (I am positive it wasn't there when I took him out of the other tank) and this morning there seems to be a little bit kind of trailing from his head (on top of his head, not his mouth or gills) I looked up some pictures of fin rot and it doesn't really look like that. I also posted this in the General Cold & Temperate Water area as well but then I realized I should have posted it here! sorry! Please help!