If you want a canister filter, the zoomed 501 would be just about right for this tank. I have one on mines and it has just about the right amount of flow. But I might have a bit more substrate and slope than most. In the end, the tank only holds a little over 6 gallons of water.
Sorry to hijack, but I have the 501 and a Mr.Aqua 12"cube, haven't set it up yet, wondering if I should just put my old eheim 2213 on it since that's what so many are using, so I'm wondering if you're keeping shrimp with the ZooMed 501 and it's adequate?