| | Re: nothing to do with aquariums question
The canister will get clogged too fast to be worth it. Ehiems work great, but when they get too much crap built up in tubes, canister and so forth, the flow suffers. An outside pond will get so much more debris in and on the water than this filter will be able to handle. You could make your own out of a rubbermaid container. This is what I did, and if you keep it clean it should work pretty good. Mine is an 18 gal. box and my pond is about 500 gal.