My Aqueon QuietFlow 55 HOB
contains those blue colored plastic pieces which are supposed to contain and grow the beneficial bacteria -- the two carbon floss cartridges slip into two "bio grid holsters" while before the water return there is a second blue "bar" piece that is said to oxygenate the water and polish it further before the water pours back into the tank, and there is supposed to be bacteria growing on this as well. When I take these pieces off to inspect them at times, or when I'm changing out the cartridges (more on that in a minute), it seems there is indeed brown "growth" all over these pieces that appear to be brown icky algae-like "thingys"...is this the actual beneficial bacteria? If so, I accidentally rinsed this bio bar thing on the Aqueon filter a few weeks back which I think caused my tank to go into a mini cycle because it got a bit cloudy (I used untreated tap water to rinse and wash it down). Since then, it seems the tank is recovering a bit and getting clear again with the aid of some Purigen and leaving the filters alone after I did a good cleaning of them (I also run an AquaClear 110 on my 60 gallon goldfish tank).
Should these bio grids and bars that come with the Aqueon HOB
's just be left alone, even if they have "brown stuff" growing on them? With regard to the floss cartridges in this HOB
-- I know it is recommended to just swish these around in tank water during a water change rather than replace them, but if the carbon is exhausted after some time in these things, can I risk just swapping them out for brand new cartridges when they become really nasty and brown...or are they brown because they, too, are holding beneficial bacteria? Should these pads/carts not be thrown out?