What do you guys think about calcium reactors?

Can you explain that to me?

Heh, which part? (starting to confuse me...)

I dose a do-it-yourself two part, like what was in the article. However, as opposed to measuring equal amounts of each part every morning and dumping it in the tank, I have a dosing pump that does that for me. I also use it to dose kalkwasser at regular intervals, as opposed to gravity drip. This is the exact model I have--each pump or "channel" allows me to dose a single different liquid:
reefdoser3.jpg
 
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