New to RO/DI...

[asylumdown]

I'm definitely putting in a RO/DI system on my new 320 when it's built, but I'm having trouble figuring out how to plumb the system. This is the system that I want: http://www.spectrapure.com/low_waste_systems.htm

However, it's looking like I might not be able to have a large storage tank in the basement, our utility room is cramped as it is, and my partner turned a hilarious shade of purple when I mentioned I wanted to put a 150 gallon tank down there, with hoses and wires running through the walls.

What I was thinking instead, was using this add on to the spectrapure system: http://www.spectrapure.com/St_alc_p2.htm,

Under my tank and next to the sump, there is going to be a 30-40 gallon salt mixing tank for weekly water changes, and a separate auto-top off reservoir. I'd have the RO unit plumbed to fill both the the mixing tank and the top-off tank, with that multi-tank shut off system. It means I won't ever have any more than 30-40 gallons of saltwater available to me at one time, but I'm hoping to not need to drain the tank over the course of it's life. I suppose I could have the RO system plumbed directly in to the sump for an auto-top off, and eliminate the need for a second tank in the cabinet, but I don't trust the shut off valves enough for that. There is an emergency floor drain under the tank, so even if something broke and the R/O system ran continuously, it would a) not go in to the sump and b) overflow right in to a drain.

Does this sound like a feasible compromise to not having anywhere to put a large reservoir for stored R/O water, or should I push a little harder with my partner? I'm trying to avoid having to do complex wiring and plumbing through the walls.