I just picked up an old powerhead while visiting my mother in California. While explaining to her what my plans were for it she told me I may not need to go through all the trouble of building a reactor due to how the powerhead itself works. I don't know the model of the powerhead Im using, it's old and covered in calcium deposits. However it does work like a charm still. Picture below shows the powerhead.
The powerhead sucks water from the tank from the open ended bottom, from there it pushes pressurized water through the clear tube that is attached to the output on the bottom, and out the larger tube near the front. As you can see, the unused airline is SUPPOSED to be hooked up to an air pump and used to mix oxygen into the water. My thought is to use that same line for CO2, my DIY CO2 setup would flow into the powerhead and mix with the water inside, then be distributed evenly throughout the tank. This would completely void any need for an external CO2 reactor and defuser! The only problem I can think of, is the impeller inside the powerhead might create a suction from the CO2 tube sucking out all the CO2 in my 2L bottles very quickly. I need expert opinions here! This is my first DIY project and it seems like its going to work amazingly!
UPDATE: The CO2 going directly into the powerhead isn't going to work, the impeller inside the powerhead creates a suction and would therefore remove the CO2 from my 2L bottles too quickly. I now plan on setting up a sump underneath the tank to house the powerhead moving water from the sump to the tank, as well as a secondary powerhead creating extreme water movement to pop the CO2 bubbles entering the sump through the DIY system. In theory the secondary sump will make the water absorb the CO2 before entering the main power head, from there it will be moved to the tank. I will do a quick ghetto setup and post a picture to get feedback.
Overall setup. Powerheads inside the yellow bucket.
The two powerheads. The larger of the two is for water movement, to absorb the CO2 into the water before pushing it to the tank. The smaller of the two is moving water at approx 160gph to the tank. Now my theory is if the CO2 hasn't been fully absorbed into the water by the time it hits the second powerhead, the travel through that powerhead and up the tube to the tank SHOULD be enough to get the vast majority, if not all, the CO2 absorbed. It may be kind of hard to see but there is a tiny little tube coming from my DIY CO2 bottles, that will be pushing the CO2 into the sump and will be placed right below the outlet of the larger powerhead so the bubbles go directly into the current. I have a THIRD powerhead I can put in the sump with the other two if it turns out to not be enough current with just two.
This is my current CO2 setup. Using two 2L bottles to produce CO2 as well as an extra chamber to catch any liquid that has made it through the process. All the tubing is CO2 resistant, and the valves are rust resistant. Check valve after the capture chamber to ensure no water flows back into my system. I may add a little something on the end of the CO2 tube that is going to the sump to break up the bubbles and make it an overall easier process for my two sumps.
Now...in my mind there is absolutely no reason this wouldn't work other than the CO2 not properly flowing in the first place. But that is a whole different problem. I believe my multiple powerhead/sump situation is going to work beautifully. Keep in mind all these products cost money, however I got it ALL free from my mother who quit the hobby after 15+ years, if added up I'm sure this would break close to even on one of the cheaper CO2 tank setups. But this is what I have, and this is what the DIY section is for :] Any feedback would be wonderful!