my DIY CO2 reactor, diffuser, mixing chamber LOL

Oooh. No, not just a filter, it's basically a mixing chamber for the CO2 that I'm piping in using that bluish tube that you see going into the gravel vac. That blueish airline hose is hooked up to my DIY CO2 under the tank. Instead of hooking up the airline tubing to an airstone and letting it bubble freely in the tank, it is now bubbling inside the clear tube and mixing with the water being pushed in by the powerhead and then out the bottom of the tube for dispersal.
 
....oh in that case....really cool.
 
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