Originally Posted by Matthew187
I bought a fluval 305 today and also purchased zeo-carb, water polshing pad and pre-filter. Should I let my old filter run while this one is running at first?
Yes, run both as long as possible. I would still run both, I do so I can get seeded media without cracking open the canister. But if you must remove I would wait 45-60 days to ensure a good bacteria exchange. I also run only fluval, you should also look into a spray bar.