RoDi

[mike31154]

If your good to waste ratio is 5 to 10, then you're doing very well, since that's a 1 to 2 ratio! Most RO membranes are designed to operate on a 1 to 4 ratio, which would in your case be 40 gallons of waste water to the 5 gallons of pure.

At any rate, I collect all the waste water as kien suggested in large plastic drums. Use in garden in summer and for toilets in winter. Folks with top loading washing machines often use the waste water for laundry. I have a newer front loading washer and it uses very little water, not feasible to fill with RO waste. I plan to replace my hot water tank soon with an on demand, tankless water heater and I don't think that will work with the system that diverts RO waste back into the hot water system. There are also RO systems which add a second membrane to recirculate some of the waste and improve the ratio that way.