Well, that is why I mix my own--at least I have a good idea of what is in it. I have noticed that if you try to dose according to calcium, it is difficult to keep up with it. If, however, you dose keeping up with alkalinity demand, it works much better--even if the calcium is on the low or high side. But, as you said, it isn't for everyone. I just like the consistency I can achieve with the 2 part and my doser. It doses it every 12 hours and maintains very stable levels. Probably not as stable as a calcium reactor, but it gets the job done.