I have a clown fish who has a small beard looking growth below his mouth. It is white around the edges with a greenish looking center. It is fuzzy or stranded looking and extends away from his body maybe an eighth of an inch in places. He seems healthy but is spending more time towards the bottom of the tank. There are invertabrates in the tank which affects treatment but my books do not show me what this illness is or how to treat it. Can anyone help save "NEMO" (clever name devised by my two year old daughter)