The kalkwasser will reach saturation levels and will not absorb any further amount of the kalk powder. What you want to do is put your ATO water in at the bottom of the bucket and push the clear kalkwasser out the top for the best results. I put a 1/2 lb of powder into my reactor and fuggeddaboudit until my alk starts dropping. You should stir the kalkwasser reservior with the pump for 15 minutes a day twice daily. For the best result, your ATO takes RO water and pressurizes the kalwasser reactor, and that in turn feeds kalkwasser into the tank. It is a bad idea to suck freshly-mixed kalkwasser into your tank - "hot dose" of alkalinity. Things die that way if you go that route. Been there, done that, got a T-shirt that says "I'm poor and depressed" after that mistake.