Shine

Heya, when using media from a running tank to seed a new one, how long would you leave the extra sponge in the old tank before transferring it over?

I don't want to just move the filter over from one tank to the next because I'd like to keep both going, and I can't put the second filter on the first tank because that would cause too much of a current for the fish....

So how long should I leave the extra media in the current tank so it picks up enough bacteria?

Lucy

At the very least 2 weeks. The longer the better
Imo, the best way to cycle a tank!

Algae Eater

Thanks for asking this question, Shine, and for the answer, Lucy! I am doing the same thing right now, only I'm running the new filter in the established tank and not just the media, and was wondering the same thing.

Jaysee

I prefer to put a piece of the used media in the new tanks filter. That way, you can add a few fish immediately. The bacteria can only grow if there is an excess of ammonia. Adding new media to a filter that's media can already get the job takes longer than it takes for a portion of the colony to multiple and colonate the new media IMO (though there are many factors involved) It takes about a day for the colony to multiply.

mosin360

I've had a sponge and biomax sitting for almost five weeks before I can finally use it tomorrow.

tremod

You could always put a piece of old media in with the new media in the filter and when the tank cycles you can put it back into your other tank. This way you still have a fishless cycle and both your tanks you will still need an ammonia source though to feed the bacteria in the old media piece.Mine took 4-5 weeks fishless.