Sorry. Misunderstood your question.

Ben is correct, I mix the kalk into a liter bottle, shake it, and pour it into my return area of the sump. A few moments later my returns spew out a cloud of kalk laden water, two or three minutes later the water is clear again.

I've been dosing like that since the end of '09. For about a year I had used the Todd method and kept my top off saturated. But the lines would kalk up and stop flowing.

Timing is important, ping advised that I should dose in this manner half an hour after lights out... But I'm asleep by then except for the weekends. So I typically dose around 4am.

Not recommended for everyone, but if used sparingly its a wonderful chemical.