Thanks for the link....Interesting about the short bursts not being good for RO/DI filter.The only thing is I'd be putting the reservoir in my basement and wonder if the aqualift would pump up to my sump.
Also are you using just the float valves,I read that you should also use the shutoff kit with it to stop production of the waste water,is this necessary?
With your idea I would just run the out put line from the filter to my Rubbermaid with a Kent Marine float valve.Then I would attach a Aqualift pump to the Rubbermaid container and have this running up to the sump all the time as a 2 pipe system like in your diagram.I could then just take the water from my Rubbermaid container and use it to mix up my water changes then have it fill back up automatically from the filter.
Thanks