Here's a long shot, Could it possibly be a sponge starting? I know your tank has been running for a while now, sometimes benthic life appears from nowhere.
Hey Matt, pick up the rock and smell it, If it's foul smelling, it's probably a Fungus Amongus. If there's NO bad smell, it's life!
-- Edited by Monty on Tuesday 30th of March 2010 09:28:25 PM
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"Earth, our Water Planet, is the only planet in our solar system to be endowed with appreciable quantities of liquid water. Life, born in the water, must be at least as rare as water in the Universe, and as such must be revered, under any of it's forms, as a Miracle."