I got a used 3 stage unit about a year ago. I replaced all the filters, though I couldn't afford a DI at the time. I have a well for water and I figured the RO water I was getting would be better than the well water I had been using. I was told my water pressure was borderline low for effective operation, but I forged ahead anyway. Lately, I've noticed the water coming through the filter seems to leave a bit of scum on the mixing pump and container. So I'm back to getting water from the Culligan machine for now. So my questions are: Will a booster pump improve the <u>quantity</u> and</em> <u>quality</u> of the water and will a membrane flush kit prolong the life of the RO? Anything else to consider? Sorry, the TDS meter is just a red light/green light affair.