Recently, my boy Angel has obtained the obnoxious habit of tail-biting. He lives in a divided 10 gallon with plants, a filter and heater. He has started this over the past month or so, he has been recovering from a previous injury three years ago with this old neighbor which sadly left his once beautiful blue and white tail into half a shredded tail he repairs very slowly so he has almost grown out his entire tail when he got in a fight with his current neighbor ( finicky divider) and left it a little torn up, since then he has not let it grow out in fact , he has shortens it and continues to bite at it and will never leave it alone! What should I do to keep him from biting his tail? And any hints on how to speed up the healing of his poor little tail?