I have the old 404 fluval .. I deep 6'ed the foam and carbon bullish and added
FLUVAL BIO MAXX.. two basket's full
ZEOLYTE CRYSTAL'S ammonia
REINA BIO CHEM STAR'S they float freely in the chamber were the foam insert would be placed . 20 star's for every 55 gal , I run 60star's on my 55 gal tank..
FILTER PEAT in a filter pouch soften's water good for plant's
NITR-ZORB great ammonia spike prevention ( rechargable)
BIO CHEM ZORB removes dissolved organic waste and make water crystal clear.. (rechargable)
blue bonded filter pad
I maintain this set up every month with a quick rinse in aquarium water from a water change to keep the bio max from clogging..
having done away with the included foam and rake my flow or force in witch the water exit's the filter has incressed greatly...