Seeding a new canister filter from an established tank with a seeded canister

[ilaizm]

Hi,

If you add a 2nd new canister filter to an established tank which already has a canister filter seeded. How long would it take for the 2nd canister filter to handle the tank on it's own?

thanks

[Duskfire Discus]

Take some media from the original, and switch it with comparative media in the other. After that, I'd say a few weeks max. You can also just let it run solo, and add a good dosing of a tank setup product like Quick Start, or any of those other bacteria in a bottle deals.

[Wes]

6 to 8 weeks to fully cycle a tank from scratch just for reference .
As Duskfire Discus said move some media to the new filter. Do some extra water changes for a couple weeks. It should fully take over in 3 or 4 weeks depending how much media moved over and the fish load .

[ericatdallas]

I'm going to say it depends. I usually take half the media from old cycled filter and move it to a new filter. Then I use the new filter as is and monitor it. I haven't ever had problems with this method. The reason is, the tank has beneficial bacteria on the glass, decor, heater, and everything else in the tank (w/ gravel and sand being huge part of it if that's part of your setup).

Then I move the old filter with slightly more BB in the tubes, walls, baskets, etc to the new tank. I would start with a smaller bioload on the new tank though.

I usually do this if I need to setup a QT tank really fast or if I find a good deal on someone selling all of their stock due to moving or leaving the hobby (has happened twice where I picked up 8+ adult discus).

The fact is, in a properly cycled tank with a lot of media is going to peak out at the population of bacteria it supports. So just by adding another filter, you're not going to get much more bacteria in the system. So once you remove the other filter, you essentially are doing about the same thing as just starting a new tank with half the cycled media.

Not sure if that makes sense.

So with that said, that's just what's worked for me. It's always important to check your water parameters though. You can always compensate for a poorly cycled tank with lots of massive water changes.