Would it work if I connected my reactor to my return pump in my sump? With the head height I have and the pipe work, I'm guessing it will be about 625~650 gph going through there...
How big is your tank /tanks? With that type of flow rate your reactor would have to be a larger diameter than 2" PVC. I suppose it could be done but you would probably be better off getting a cheap power head and running it through a reactor. The price for a 1 foot long piece of 6" PVC pipe would probably cost more than the powerhead. You would probably need more than a 1' piece to give the CO2 time to diffuse. You would also need to have the flow go into the top and out the bottom otherwise the bubbles would shoot through the reactor.
DIY External Max flow rate 
Linear Mode
