Any filter media from a well established tank will hold millions of bacteria. Just enough to seed your tank. I wouldn't put the whole filter on, you don't want to crash your other tank. What I do is remove a Bio bag from my canister and put it in the new filter. If you don't have Bio media then remove some floss or coarse, wring out the poop in old tank water, get it at least half way clean. Pop it in the new filter and let 'er rip! You could probably have the new tank cycled in 3 weeks or so. Don't take too much media from your established filter or you could run into a mini cycle.
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