DaStaCo. Expensive but easy to use. The cost of setting up a Calcium reactor with a regulator, Dial-aBubble, pH meter, feed pump is close to the same $$ as the DaStaCo, + CO2, unless you find a deal for a used calcium reactor set up with all the bells, a new DaStaCo is a reliable way to get your alk stable.
Just my opinion, I have a calcium reactor and all the other stuff and I wish I knew what I just told you before I started fiddling with a calcium reactor