Increasing calcium and alkalinity in my tank

I started to dose kalkwasser in my tank to help maintain my calcium and alkalinity levels while also increasing my pH slightly since its a bit low. Kalkwasser is white powder that when mixed with water has a high calcium, pH, and alkalinity level it is basically pickling lime water that our grandparents would use to can vegetables but the pickling lime water is very hard to find these days.
In the picture below the tube on the right is the tube used to drip the kalkwasser into my sump. Attached to that line is a plastic piece that allows me to control the speed that my kalkwasser drips at much like an IV at the hospital. To start the kalkwasser all I have to do is blow in the tube on the left and the kalk drips out the tube on the right.
The only problem with this is the kalkwasser tends to settle over a couple of hours and you need to stir it. I remembered that I have an old hard drive (which have powerful magnets inside that help spin the harddrive) and some high strength magnets encased in plastic. So I made myself a magneting stiring device, only problem is the harddrive died on me when i placed the kalkwasser on top.





Oh well, back to the drawing board.