The Korallin Reactor is a quality piece of equipment, and it should give you good service. They are not inexpensive. They use Eheim 1048 pumps for recirculation. You will probably find that this model works like any other decent calcium reactor on the market, whether it is MRC, Korallin, GEO or any other brand.
All calcium reactors (regardless of brand) can depress tank pH because of the low pH of the effluent. CO2 gas + Water = Carbonic acid, read acid, < pH 7. You can direct the effluent into an area that gets good aeration, like the input of a protein skimmer. Or you can dose Kalkwasser to counter the effects of the pH depression.
