You can certainly go with a canister filter with a sponge filter on the intake
; but small canister filters are sort of expensive and don't usually have a lot of media so they need to be cleaned often. For my 10 gallon I use a Aquaclear 20, they typically sell for about $25 new. They do about 100gph and are adjustable to slower rates if needed.
I like them for five reasons:
1) The media is stacked horizontally which allows it to hold DIY CO2 bubbles fed into the intake;
2) I use two sponges for maximum bio-filtration
3) Most parts including intakes, impellers, shafts, along with media are available at most LFS
4) US based customer service with a toll free number to call and I've used it a few times and it works!
5) A lifetime warranty
And for shrimps don't forget a sponge on the input tube strainer.
10 gallon with Aquaclear 20 HOB filter