Somewhere, I read that bio bugs are not visible to the naked eye because they are too small. But recently, when I peek into my OHF of my 2ft tank, a bunch of brown and hairy stuff grow on the filter media. These are not brown or hair algae, I sure. I suspect these are the bio bugs because ever since they appear in large quantities in the OHF, water cloudiness in my tank is gone...whatever other new media I put into my OHF will be covered by this brown muck overnight. I believe these are the "good" stuff rite?

See the brown stuff covering my ceramic rings?