Would someone please explain the difference...

[kahuna]

... between a kalk reactor and a calcium reactor?  I'm confused.

Thanks.

Kev

[ohioreef]

A calcium reactor breaks down a calcium rich media using CO2 to regulate the Ca and alkalinity in the tank.

A kalk reactor passes the top-off water through lime, usually pickling lime, to regulate the Ca and alkalinity. A kalk reactor saves you from having to actually mix limewater for your top-off.

[kahuna]

Is there an advantage to one method over the other?

Thanks.

Kev

[Slicktrax]

price.  you can setup a diy kalk drip system for next to nothing.  most reactors will be relatively expensive to set up.  chemically i think you get the same basic end results.

[verper]

A calcium reactor can keep up better with a SPS dominate system as it uses the tank water and CO2 to break down dead coral to make Alk and Cal.  With its use, you can experience a drop in your Ph, but not always.  Depends on how you plumb it and the type of reactor. 

A kalk reactor uses makeup RO water to add diluted lime (which just happens to have exactly equal amounts of Alk and Cal) to your system.  With its use, you raise your Ph and are limited in how much you can add by the Ph increase and how much makeup water you go through in a day.  One advantage of using lime water is that it also precipitates phosphates.  Downside is it will not keep up with an average/heavy SPS tank need.

Some use both to compensate for the lowering/raising of the Ph.