Filter without fish...

[steve b]

So I have fish less cycled a large external filter in a small tank and now need to move it and plum it into my 5' tank which has no fish in it yet. How long would you say a fully cycled filter will last before the bacteria dies off and have to re start again? Don't want to add Ammonia to the new tank as it has a 0 Nitrate reading of the water and don't want to have to start changing water.

[brewmaster15]

Steve when you were cycling that tank you got a fair indication of how much ammonia needs to be present to.maintain that filter. If you stop feeding it for even a few days you are going impair it alot.

I would keep it on the small tank and continue feeding it until you need the filter on thr big tank.

[steve b]

Yes that's what I thought, maybe reduce the Ammonia down a bit, as there will only be about 10 fish in the 5' tank to start.