How long to seed filter

[ai823]

Kinda of a dumb question but.. I took the filter media out of the sump on my smaller tank which is 175 gal with like a 20 gal sump and temporarily shut it down, the media is mostly bio balls and foam.. I put it in the 110 gal sump of my 420 gal. The 420s filter media consists of 1 large 2” thick foam pad,2 filter socks, a bunch of bio balls and matrix. My question is how long would it usually take to seed the 420s media with bb before I dare remove the 175s media and get my other tank set back up??

[Willie]

If you just moved half of the media, then both tanks are immediately cycled.