Another timer option: Tripp Lite TLP74TG Eco Surge Protector Green Timer Controlled 7 Outlet 4ft Cord .
I've been using this one for a couple of months and I'm very happy with it. I use one bank for lighting and the other for the CO2 solenoid.
CO2 on at 4am, lights on at 6am, both off at 8am. CO2 on at 3pm, lights on at 5pm, both off at 7pm. Works great and reasonably priced.