How long to seed new filter

[FemaleBettaLove]

Hello,

In my cycled 10 gallon tank, I have both its filter and a new filter for a new quarantine tank. The new one has ben in there running for about a week; is this enough time for the beneficial bacteria to colonize the new filter?

Thanks (I'm new to this)

 

[Aiken Drum]

Leave them both in there running alongside each other for 3 weeks. You will still be removing some beneficial bacteria when you remove the old filter, so regularly check your water parameters after doing so and do water changes when needed until you are confident that your cycle has re-established properly. When you take out the old filter squeeze out any sponges into the water, and if your new filter has any unused capacity, move any filter media from the old into the new also.