DIY canister filter for nano

[blasterx]

I'd like to get your input on an idea I've had. I'd like to add some extra bio filtration in my 12g nano but don't have any idea how I could manage to build a sump with a tank like that that's already setup and almost a year old.

I tried to buy a canister filter off ebay but that didn't work out too well. I was going to fill it with live rock and I thought that would also give the water a little more movment as well as provide a little extra filtration.

So here's my horrible little drawing