You CAN restart your canister after 1/2 hour, I would recomment you keep it running on a bucket full of your original aquarium water, or better yet run it on the pond.
After a month, there is probably not too much in the way of anerobic bacteria, but I could be wrong. You could completely rinse the stuff, as if it were new and put it back.
Put the plants and the fish in the pond throw a light on it if you can, with the old water if you have any, if not try to match the conditions and add new water. If you have a heater running in the pond, make sure it does not touch the sides of the pond, or anything else for that matter.