Ro product water to 2 storage barrels?

[DiscusZ]

I want to fill 2 45 gallon brute barrels for RO storage. whats the best way to plumb this?

I currently use my Apex, with a solenoid to turn off water in barrel when float switch is closed. I also use this same barrel to auto fill my ATO 5g bucket beside the tank . (RO storage is in basement and tank is 1 floor up)

I have attached a simple diagram of my water change system

Green things are valves so depending whats open/closed dictates which water water flows

I can pump water from RO to my SW storage, I can mix my SW, I can then pump SW to my tank

RO storage has 3 Float switches attached to my APEX (High, Med and Low) RO production starts when Med Switch is OPEN I want a second 45 mainly for my SW mixing and leaving the other for ATO

Hope this makes sense

Thanks