DillonMcCain
Aquarium Advice Regular
I have 3 freshwater tanks. I have grey fuzzy, hairy stuff growing all over everything. Is this harmful to my fish?
No it's called black beard algae from what your describing. The only problem is it grows very fast and is impossible to get of live plants. I now have no live plants as this algae covered all the leafs of all my plants killing them all. Sorry to tell you the bad news and it does not harm fish or effect water conditions at all.