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Conflicting Answers: Is Sludge On Filter Holder Good Or Bad Bacter

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Nov 19, 2012
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I have over the back hanging filters for my two 2 gallon aquariums. Sometimes a little sludge gets stuck on the plastic that the filter cartridge sits in. I normally clean this off in the sink. Not back into the tank.I received two conflicting answers from the same Pet Store Chain, but from two different stores.One told me to wash it off.The other, told my husband that this is good bacteria and shouldn't be removed.My Ammonia levels are good and tanks are clear. I have photos of the sludge I can upload tonight.It is a darkish green/brown in color.Opinions? Thank you.
i know in sump's that you can have a thick layer of sluge once it settles it helps because nitrifying anaerobic bacteria set up in it these turns nitrates to N2 i think (at least thats what i read about im marine systems), but the sludge needs to not let oxygen in otherwise this wont happen, the down side to it in normal filters is that it bung's them up slowing down the flow and therefore reducing the effectiveness of the filter because it reduces the surface area which your bacteria lives on, thats as far as i understand it but im newish to the topic as well
I have always cleaned the inside of my filters. If you don't have any spikes in ammonia or nitrite, all is good.
The sludge isn't the bacteria, you can clean it off, just don't use tapwater to do so.
The sludge can also clog up the flow, which is bad. The bacs you want for dealing with ammonia/nitrite require oxygen and water flow, so it certainly helps to keep the filter running efficiently. Just don't use tap, as already mentioned. A quick swish in the old tank water you remove it sufficient.
Scoop out a jug of tank water to wash the sludge off in, then give that to your house (or outdoor) plants - mine look great since I've been doing this!
If you're doing this just before a partial water change, you'll then be able to top up with treated water.

Sorry, forgot to say - in the filter, the part where most of the good bacteria live in is the gravel chalky looking stones part - all filters are a bit different, but I'm on my 3rd (not including under gravel system) different make and they all have similar basic workings and filter media.
the answer doesn't much matter....just wash it off....

the most beneficial bacteria is in your filter media.....thats all you need

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