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I don't see why not. Its just plumbing at this point. I guess the question is why do you feel you need one? If its to combat pH drop, you can make sure your dripping it in close to the skimmer, or put the effluent in a cup with an air stone.
My opinion is as with everything in this hobby, just an opinion. Ask on RC which is the best reactor and Geo comes up a lot, single chamber, its what I'm running and have only positive results. Don't chase ph.
Only clear winner on Calc reactor is get a Aquarium Plants regulator. No one will disagree on this point. Others will work, just that much more difficult to dial in and not as reliable.