I have the following equipment and want to add SWG and in the process automate the equipment and make it easier to switch between pool and spa and control the temps.

Pool is 26K and spa must be around 4-5K gallons

Pump: Pentair Variable Speed (4 speed)
Filter: Purex 4000 series DE filter (10 plus years old but really well kept and serviced)
Heater: Purex Mini Max Plus heater (10+ years old with rotary knobs for the temp controls)
Pool and Spa each has 1 LED LIght with many color combinations

I was thinking to go with the Hayward Aquarite chlorine generator with the T-Cell 15 for 40K pools but upon further review and paying only $200 more I can get the hayward PL-Plus Automation and 40K gallon chlorination.

I will also purhcase 2 automated valve actuator (preferably Hayward)

and connect the puzzle together for an easier single control center for all our needs and if need be a remote control to have handy?

I am not sure how to add the current older heater into the control unit or will I have to purhcase a new heater to use thru the new controller?

Your comments and ideas are welcome. Located in Southern California.

Thanks