After ten years of keeping fish, I've been looking to start over and do a major rehaul on my existing 55g. New fish, new substrate, new plants, all new. My main question is if I am changing the substrate (and old filter, decorations, etc.) how can I seed the tank with some of the old bacteria to give it a healthy head start? Maybe I could leave on the old filter for a while, and then add the new canister? The filter has kept a pretty steady supply of bacteria, but I wouldn't know how to keep it healthy if I switched filters. Is there a reliable and simple way to seed a new setup in an old tank? If I could get a step-by-step, it would be very appreciated!