Best Filter for 30 Gal tank

Canister, a single H.O.T. Magnum 250 should be able to handle the tank. You could choose to use the bonded sleeve method, but the micron cartridge (re-useable) run 24-7 isn't such a bad idea. Though in order for that to work, you have to have an additional micron cartridge, and alternate the two. A Rena XP2 should also prove decent filtration for the tank, though for alot more money, yet another option is the C-220 as well

BTW, should you choose to run the 250, one or two Rena Fil-star foams work as wonderful bio-media. That's one I've done with my 350.
 
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