Buying RO / DI - I know nothing

[Snaz]

Thanks for the help guys. Looking further into that Costco link Macky provided I came across this interesting fact.

"While standard reverse osmosis systems waste 15 or more litres (4 gallons) per every 4 litres (1 gallon) produced. The new patented "Zero Waste" reverse osmosis system wastes no water. "
http://www.costco.ca/Browse/Product....835&lang=en-CA

Is this correct, how do standard RO units waste water? Surrey residents are metered for water use so wasting four gallons to produce one seems costly and not very "green".

[hillegom]

I see that link to costco has a pic of the unit. This is a new system and I have not seen one yet. I guess it doesn't waste water as it uses the pump, electrically operated, to push all the water through the RO membrane. But this would coat the membrane with all the "bad" molecules you would normally pass out to the drain. So I would check to see how long of a life the membrane is rated for.
Normaly, Ro units make one gallon of good water and 4 gal down the drain. This will flush all the bad things down the drain, and this will lengthen the life of the RO membrane .
You could always plumb the drain water outside and water the lawn. Good only in the summer though!

[animalcrossing]

ive picked up a unit on e-bay for 99.99 plus from aquasafe/pure and ive had good luck so far

[alfredshouse]

http://www.jlaquatics.com/product/RO...+-+50+GPD.html
just a thought.