any of those 3 will do. however most of the time people dont use sumps on small tanks. people normally use sumps in big tanks. most people on here choose canisters filters like eheim, fluval etc...just to name a few brands. and hang on the back filters will do too. depends what you can afford. if your on a budget an ac110 hang on the back would do. or 2 ac70's. but i would pref get a canister filter. make sure you shop around craigslist and ebay for the best deals.