I use a Megachlor with Cl2 detection in my 450 gallon spa for the same reason. Works great!I believe it would be cheaper and more effective to control the SWG with an Intermatic timer. With so few adjustments necessary for the SWG, it seems silly to control it with automation. I adjust mine no more than about once per month, increasing as the weather warms and decreasing as it cools. The RJ 60 model would allow for the most Cl2 production at the lowest rate setting, thereby preserving cell life.