I have been using Flow-Max Filters for many years to clean water in Haiti and Cuba. We typically use the 2 ¾” X 20” pleated filters in 50 micron, 5 micron, 1 micron and 0.35 or 0.20 micron. I have checked your website, but cannot find any performance data from the manufacturer on how well effective these filters are against cysts, e coli, cholera, and other water borne bacteria/pathogens. Can you help me with this kind of information?

The Water Doctor Answered:

You can’t find it because it doesn’t exist. There is no data. They are not NSF Certified, therefore there is no testing. It’s what they say it is… if you care to believe that.  That’s part of the reason we are no longer selling Flow-Max Filters.  There is little or no performance data on them, they are not NSF Certified, and frankly, our testing shows that they don’t do what is expected.

In fact, they say “Made in USA” on the label, but I have been told by people that work for the company that they are not made in USA.  I have my suspicions, but I don’t really know.

What I do know, is the following:

1. Pleated filters like Flow-Max are absolutely the best water to filter water that contains significant amounts of sticks, stones, fish turtles or actually: sand, silt and sediment.
2. Flow-Max filters are not NSF Certified, which should immediately raise a red flag.  I mean, we are talking about your home water filters or your businesses water filters, shouldn’t you REQUIRE that a filter you use for that be NSF Certified?
3. For a filter to be NSF Certified, it HAS to meet the testing protocol of NSF.  Then, when you publish your specifications, consumers can rest assure that what you say is the way it is.  AS an example, if a company says that they have a .35 micron absolute filter, you can rest assured that that it will remove over 99.98% of everything over .35 microns.  Without NSF Certification, you can say it, but is it true?
4. That’s why we sell Harmsco.  Their filters are NSF Certified.  You can take what they say to the bank.
5. Harmsco is bigger, badder and better.  Take a 2.5″ x 10″ pleated filter.  If you cut it apart and stretch the media out, you will find that the Flow-Max filter had 58 inches of media.  Does that sound good?  Harmsco has 91 inches of media that is more robust.
6. Harmsco filters better, last longer and can be cleaned and reused more often.

Guess which filter we now sell?

Case-in-point:  I always try different reverse osmosis systems at my home and after trying the nextRO for several months, I replaced it with a permeate pump reverse osmosis system (50 gpd membrane).  For your information, my TDS (Total Dissolved Solids) are around 540 ppm.  After 8+ months, I was really discouraged because my TDS routinely remained at over 100 ppm.  If I drained the system on back-to-back days, I could get it down below 50 ppm, but it would rise quickly again.

TDS creep was winning the game.  In case you don’t know what TDS creep is, it is defined as follows:

“The natural diffusion of TDS ions through the membrane from the feed side to the permeate side when the feed pressure is shut off (i.e., when the tank is full).  This effect results in lowered water quality.”  -  A Practical Application Manual for Residential, Point of Use Reverse Osmosis Systems by Robert Slovak

Now, before we go any further, it needs to be understood that a permeate pump reverse osmosis system should do the following:

1. A Permeate Pump RO should make water faster than an ordinary RO
2. A Permeate Pump RO should make higher quality water than an ordinary RO
3. A Permeate Pump RO should waste about 80% less water than any ordinary RO
4. A Permeate Pump RO should deliver the highest pressure at the faucet of any RO

Well, my pressure was good.  Excellent actually, as I was feeding two ice makers, a kitchen faucet and a humidifier.  It makes water very rapidly and I know that it wasted less water, but the water quality was horrible.  Additionally, we have several customers who were not thrilled with their water quality, just as I wasn’t.  What to do….

Everyone told me that the Aquatec 1000 Permeate Pump was the “cat’s meow” but the results were less than stellar.  After months of fighting this issue, I decided to try the “old Aquatec 500 Series Permeate Pump” which is designed for membranes up to 50 GPD.  Not a 75 GPD or a 100 GPD, but just a 50 GPD.

So, I changed the permeate pump ( a 2 minute job).  Then I drained my reverse osmosis tank (the TDS was reading 114 ppm).

When I got up the next morning I checked the TDS and it was 18 ppm!  From 540 ppm to 18 ppm… not bad.

It has remained below 25 ppm since then and we have made a decision at US Water:  We will sell a 50 GPD permeate pump with an Aquatec 500 Series Permeate Pump, not a 1000 Series.

Here’s what bothers me: Why can’t the engineers at Aquatec (who makes the permeate pump) and Watts (who USED to make our permeate pump RO system) figure this out?

All 50 GPD Permeate Pump Reverse Osmosis Systems from US Water now have the Aquatec 500… and exceptional water quality.

This is a public service announcement brought to you by The Water Doctor!

Oh… the 500 is also quieter than the 1000…  duuuuhhhhhh!