I would say, just in my experience, DIY
CO2 isn't really worth the fiddling. You can grow lots of plants just fine with low-medium-ish light, and the DIY
CO2 is so inconsistent. Get a cheap
LED light, Finnex or Beamswork I think, put it on a little timer so you can measure/regulate how much light you use, and dose some liquid fertilizer/liquid
CO2.