I'm replacing my old quietflow 10 with a canister filter. The canister filter comes with bio balls but I plan to toss those and using a bag of rubble rock. Will I kill my cycle by doing this? I'm putting all the filter media in the quietflow 10 into the canister just in case plus I have a backup sponge filter in my tank. Should I be doing anything else? My tank is 4 months old.