I had great success for almost 10 years with a GE and Whirlpool under sink RO system when I was running a 50 gal mixed reef. I would fill an empty 1 gal jug, then pour it into a 5 gal gas can style container. It was tedious, and the under sink reservoir only held a little more than 1.5 gal and took a couple hour to refill. I moved from VA to TX and had to shut that tank down. When I set up a new 75 gal a year ago, I budgeted an RODI 4-stage from BRS. It produces 5 gal an hour. So much more efficient and better than what I had set up before (I didn't understand benefits from 0 TDS. I set up on my patio with the garden hose attached and collect the waste water to use for watering plants or pool top off. Some of the best money I've spent.