How it works is very simple, much like a commercial canister on a much smaller scale. An airline siphon tube from the aquarium runs to the top of the canister into one of two airline T's. The top was drilled with holes slightly smaller than the OD of the T's for a press fit, then sealed on the inside with GE 100% silicone (a very small amount just for insurance). A tube on the inside runs down to the bottom of the canister, under the drilled dispersion plate (which is simply the top of the 2 liter Matrix jar which just happened to be a perfect fit). The other T is in the center of the top. Airline tube will run from here to the Tom pump that will hand on the back of the aquarium. Very, very simple!
I already had the canister, T's, tubing and 2 liters of Matrix.
Tom Aqua lifter pump: $15.99
Tom hanger: $ 8.99
2 Liter Seachem De*Nitrate: $21.58
Seachem Stability: $ 8.66
S&H $ 0
Tax $ 4.42