My old system was completely automated with kalk, 2 part(well 3 part because it was brs) and ato. All were separate functions. You really do need a controller and stirrer(kalk) or a separate vessel fir storing your kalk mixture. It's pretty simple actually. You ruin your ro/di output to a say, 5 to 10 gallon aquarium (I used a 10 for my 110 dt) with a float valve. You need, on your ro system to have a tds meter or two to watch your di resin. Then, from that, you run a small powerhead to a kalk stirrer. I used a magnetic stir that came in for 30 seconds every hour(I wanted it to stir the kalk, but I didn't want it to be the super saturated and cloudy solution). I then set my controller to not stir and dose top off at the same time(a controller is almost needed for things of this nature) and if the stir came on, to wait(delay) the top off/feed to the stir for 5 minutes. Then, that feed is what I to my sump.
I set it so that the feed pump would only stay on a maximum of 30 seconds (that is one of the failsafe), then cycle for 5 minutes, and if it cycled, to send me a text and also a visual and sound alarm. There was no reason fir it to cycle or run more than 30 seconds unless something was wrong. Also, for your ato in the sump, be sure to run 3 float switches (high, low and emergency). I also ran, on the floor of my stand, and on one of the walls of the sump chamber, leak detector sensors that would send alarms also, and shut the water completely off (you could set it up to send water to a powerhead to drain water also if you wanted just depends how much emergency room you want, and mine was in the living room also).
Even with all this, the only thing visually my woman saw, was the 10 gallon tank, and even that, I painted black (because of the size of my sump and I couldn't fit the 10 gallon in my stand). But everything was done internally to the sump, 10 gallon tank, or downstairs at the ro unit. Given, I ran 40 feet of water line, but with a Booster pump, it was nothing at all..
