Figured that'd be the case. Here is where a large canister fliter would come in really handy. With all that cycled material in there you'd be able to transfer your fish all the media and get all your new filtration on line without skipping a beat. Then just add new fish slowly to acclimate your system to the increased bioload. Might look into getting a used fx6 or other large canister or just do a diy on top of the tank with all your filter material in it. Take it down when everything is running smoothly.