so i have a tank, around 350 litres the filtration at the moment is a 2000lt/h internal filter and a 700lt/h powerhead. i want to swap the internal filter for a canister of some sort. and i am hoping to keep a small group of firemouths, some larger catfish and possibly a small school of mollies. so far i have looked at a fluval 405 + another powerhead and an fx5. any suggestions or recommendations, anyone? cheers.