Tank Upgrade Advice Needed

[lil_clownfish13]

So...

I have a 10 gallon nano-reef right now, and its filtered by a Fluval 1 internal, a Powersweep 220, and an Elite mini powerhead. I am hoping to upgrade to a 20g tank this summer, and am wanting to purchase a fluval 104 to do the majority of the filtration, and retain the powersweep also.

What im wondering is what people think of using an external canister as the mainstay filtration for a reef tank. I don't want to do a sump for this tank because of its location.... any advice??

thx so much!!

Tina