Silly question, lighting?

I recently set up a CO2 for the first time ever. I got the 10 lb tank at a local gas supplier, they normally fill tanks but they also sell them, for about $90 full. I bought a new regulator / solenoid / microvalve on e-bay for about $85. I am using an air stone while I explore the wonderful world of diffusers and reators but any of them can be had for about $20 and I'll be done. I plugged the solenoid into my light timer because I see no reason to run CO2 when I am not also providing light. I just used one of those 3 plug adapters to let the solenoid and lights work together on the same timer.
 
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