View Full Version : Two part or Kalk reactor, whats better and why

09/06/2017, 08:28 PM
I have always used two part (ESV or Seachem) but was thinking of going to a kalk reactor thru my top off. I use a Spectrapure top off, so the kalk will not ruin the pump. This seems like a simpler system, but maybe 2 part would be more consistent. I do manually dose Magnesium as needed and my two part is dosed by an Apex (plug 4 & 8), but I am always concerned the Apex timer will malfunction.

09/06/2017, 10:29 PM
Kalk often can't keep up with a tank's demand for calcium and alkalinity, but it does have the advantage of leaving the SG unchanged. Two-parts all increase the salinity, which sometimes ends up requiring a bit more maintenance. Kalk also is high in pH, which can be helpful for tanks that run at a chronically low pH. It can be problematic for tanks that have a variable evaporation rate, though.

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09/07/2017, 09:42 AM
Thank you for the information.

09/07/2017, 12:18 PM
I've used kalk as the mainstay for calcium for alkalinity for many years. I like it's pH raising effect and self purifying qualities. I dose it from a still reservoir via a spectraprue litermeter 3 at a daily level( in 150 increments ) aprroximating top off . A little two part makes up any shortfall in alk or calcium.