In , Pete
empowered us with this mighty blow against the
Patriarchy:

If you want longer term CO2 creation try the ideas at
http://www.thekrib.com/Plants/CO2/

I'v got a DIY CO2 setup with 2 huge cranberry drink bottles (2.5 L each)
joined together that feed into the intake of my canister filter (I'v
punched a hole in the intake tube just below the water line to feed the
CO2 in).

Pete, could you elaborate on how you attach your CO2 line to the intake
tube? What do you use for a valve, how do you seal it, etc.?