Yes, any media from the main tank will allow for a transfer of bacteria. Be sure the fluval has not stopped for any length of time though. The lack of O2
will in the canister will kill the bacteria. Also be sure to rinse the "rings" in SW
removed from the main tank to remove any excess detritus that may be trapped in the rings. You do not want to add any organics that might hamper water quality. Do not use fresh water as it will kill the bacteria outright.