Kalk with magnesium stearate dosing?
 

As commercial kalk (calcium hydroxide) clumps, can we mix magnesium stearate with it? Will it be harmful? Brightwell has a kalk +mag supplement. How to diy it?

Sent from my Moto G (5) Plus using Tapatalk

The magnesium will precipitate if it's ionic. I wouldn't add magnesium stearate to a tank, in any case. I don't know what it'd do, but it's basically a soap-like sort of compound, which could be quite toxic. The Brightwell supplement doesn't work to add magnesium unless you dose the precipitates, and it's not clear that they add any magnesium to the product. It's probably present as an impurity.

Do people have trouble with kalk clumping? The solution forms clumps or the anhydrous powder clumps?

For diy kalk and mg supplement, I would use pickling lime and magnesium chloride (or magnesium sulfate in small amounts), and dose separate solutions of both.

I didn't have problems with Kalk clumping, but I live in an area with moderate humidity. It will convert to calcium carbonate over time, but the process generally seems to be very slow.

Thanks. That has been my experience too. I store my powder in an air-tight container, and that probably helps.