I dont have any room under the tank. The tank is on a wall in my living room... If my wife sees something like your explaining then I'm going to be in serious trouble.

I'm not sure what my best option is. I'd like to have a simple system but I cant figure a way to do it without making it complicated and running lines in the attic. I'm thinking that the temperature of the small amount of water in the lines wouldnt effect the 160+ gallons in the tank and sump, but I really dont know.

Wow I need advise!!! The closest place to store any quantity of water is in a closet of my guest bathroom, which is going to be pretty far away (Im geussing 40-50'). Of course I could put the RO/DI and water storage on my back porch but that would be bad news in the summer and winter.