chasingtime
Aquarium Advice Newbie
i just bought a rena xp3 for my 220 fw. i am way understocked and would just like to run this filter only. i have purchased more foam insert and intend to use only course foam and then finer foam for final filtration. i am under the impression that foam is a great mechanical and biological filter, if so why would i use bio balls or similar item in place of foam? i have 2 emperor 400s but would like to run the xp3 only, it says rated for 175 gallons but remember i only have 2 5 inch chain pickerel and 2 smaller largemouth bass.