I thought it would be neat to start a topic where everyone can show off their PVC CO2 Reactors and tell everyone about their design. How it works and what they would change. I thought this would help people out knowing what works and what don't work.. I will start I just made on it's kinda larger than I planned on but the shortest piece of 2" PVC I could find was 2'. It ended up being 38" I plan on hiding it behind my stand it will fit nicely behind there. I used two T's on each end with 2" to 3/4" Pipe bushings in each spot. The top fitting is where the water goes in then on the same T there is a 1/4" compression fitting for CO2 injection. Both water connections are made using 3/4" hose barbs 5/8" hose goes onto them with a little work. The bottom is where the water exits and the very bottom of that T is a 3/4" plug so I can hold the reactor over a bucket and drain it it I ever need to. It holds around a half gallon of water. This one is a monster I have it going to the inlet of my magnum 350 and by opening the valve for the C02 port it will suck air and take a really long time before it actually sucks enough air to get air bubbles going into the filter. So I am thinking that with just a few bubbles a second it will work fine. I was going to put this on the outlet of my filter but did not have the enough hose to do it that way. I am using the 3/4" hose barbs hoping it reduces the flow restriction. You will also notice that I used pipe thread adapter on the pipe and the T's this is so I can always change the length or change it to clear PVC if I feel like at a later time. Withought building a new reactor.