Planted Tank Guru
Join Date: Jan 2008
Location: Santa Clara, California
Install a check valve on the tubing of the DIY CO2. When you want to "turn it off", just unplug it from the check valve. When you wake up, plug it back in. It'll take a couple hours to get enough pressure to see bubbles diffuser though.
Eheim Classic 2213
Eheim Pimp #341