If I take a sponge filter and place it in a cycled tank and leave the old filter in as well, will good bacteria grow on the new sponge filter even if it is not hooked up to an air pump? I am asking because I am intending to put another sponge filter in one of my tanks but I don't have another pump for it. My other sponge filter has a pump but is across the room. I'd like to get the sponge started with bb so I'd like to put it in the tank now so it will already have bb when I can get it hooked up in a week. Is this viable?
Oh, Also, how long do I need to wait before removing the old filter? Would it be sufficient if, when I get the sponge filter running, to cut up the spong from the old filter and stick it in the sponge filter?
This isn't a new tank. Its an already cycled tank. I am just looking to change the filter to a sponge filter. But right now the sponge filter isn't hooked up to an air pump its just sitting in the tank while the old filter is running.
The time for a non-bubbled sponge filter to work - in a cycled tank - is 4-6 weeks according to AngelPlus.com, where I buy my sponge filters. I mean you can leave it in the tank without an air pump for 4-6 weeks, then take them out to cycle a new tank. It is faster (I think 2-3 weeks on my 20G cycled tank) if the sponge filter is attached to an air pump, however.