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THE REVERSE OSMOSIS MEMBRANE
Cross Section of a Typical Membrane
ROcsmem.jpg

How the R.O. Membrane Works:

When the reverse osmosis system is operating, feed water flows into one end of the membrane housing element as shown above. It flows across the wound membrane. Because there is pressure on the water, reverse osmosis takes place. Water flows through the membrane to the core, while the dissolved minerals remain on the feed side. The water that flows through the membrane is called "permeate". The permeate, or product water from the membrane, is now safe to drink. The rate of production is relatively slow. Normally a storage tank is used hold the finished water until it is needed. When the tank is full, the system will automatically stop making R.O. water.

Not all of the water flows through the membrane. Only 25-50% of the water becomes permeate. The remainder stays on the feed side of the membrane and flushes away the dissolved minerals. this water is called the "concentrate". The concentrate plays an important role in the operation of the membrane. As the permeate flows through the membrane, the concentrate retains almost all of the minerals that were in the original feed water. The TDS (total dissolved solids) of the concentrate rises. As it flows past the membrane, it carries away the minerals, in effect washing the surface of the membrane. It is eventually piped out to the drain. If the concentrate did not carry away the minerals, the membrane would foul or plug-up, acting like a filter which fills with particles and must be changed. Proper concentrate flow across the membrane will generally mean many years of high quality water from the membrane.


Comparison of the sizes of materials rejected by reverse osmosis membrane.

ROpores.jpg
APPROXIMATE REJECTION RATES OF VARIOUS IMPURITIES:

DISSOLVED SOLIDS

Removal %

DISSOLVED SOLIDS

Removal %

Aluminum 99 Magnesium 99
Bacteria 99 Manganese 99
Barium 92 Mercury 97
Bicarbonate 98 Nitrate 93
Bromide 96 Organic Pesticides 99
Cadmium 98 Phosphate 99
Calcium 98 Polyphosphate 99
Chloride 98 Potassium 96
Copper 99 Radium 80
Cyanide 95 Silica 90
Detergents 99 Silicate 96
Fluoride 98 Sodium 96
Iron 99 Sulfate 99
Lead 90 Zinc 99

To SEE How To Install a typical Reverse Osmosis System


We recommend this fine YouTube video produced by Water2Buy.co.uk http://www.youtube.com/watch?v=2eBCggg_jaI

For basic filter change explained


We recommend this fine video on YouTube, http://www.youtube.com/watch?v=9_ZY0yHnejg


For basic membrane change explained


We recommend this fine video on YouTube, http://www.youtube.com/watch?v=SHs-W0wJOZg



Housing Clip ( one ) - RCL068 for standard Membrane, PN RP2500. Silicone 1 Gram Tube Lubricant for O-rings
Housing Clip ( one ) - RCL068
IN STOCK
Your Price: $1.00
Clip, individual, ( you might need TWO ) to attach the standard Membrane Housing ( PN RP2500 ) to the metal unit plate.

One gram of food grade silicone for use with o-rings, gaskets and seals.
Enough to lubricate about a dozen or more o-rings and seals.
These tubes come from one of the leading valve manufacturers.

Liquid Sanitizer Concentrate for sanitizing Water Softeners, RO Units, and Water Coolers.
Cleans and Restores Your System
O-ring Set of Two NF-RO-ORING used with System NRO4-50 Fitting JG - Drain Restrictor Elbow 1/8 m x 1/4 tube
Oring Sump Big Blue DM151122 OR-100
IN STOCK
Your Price: $5.99
O-ring Set of Two for housings used with System NRO4-50. as EACH housing uses a DOUBLE o-ring pair.
So, you'll want to order TWO SETS ( for a total of 4 o-rings ).
Oring Sump Big Blue DM151122 OR-100 Drain Restrictor is built into this 1/8 male thread x 1/4 John Guest Elbow used commonly in connections to RO membrane housings and the drain line.
* Note: Soon to be Obsolete: As of July 21, 2017 we only have ( 1 ) left in stock.
Housing for standard Membrane, PN RP2500. <br>Should fit all reverse osmosis membrane - standard size 1.75" X 11.75" 20" x 2 1/2 " 5 Micron Pre-Filter Spun DC155016 Automatic Shut-Off  ( ASO ) Valve w/JACO fittings
Housing for standard Membrane, PN RP2500.
Should fit all reverse osmosis membrane - standard size 1.75" X 11.75"
20" in length and approximately 2 1/2" in diameter with a 5 Micron rating.
Pre-Filter Spun - Poly used in large commercial reverse osmosis systems and some home whole house filter housings.
Automatic Shut-Off  ( ASO ) Valve w/JACO fittings
Carbon Block  20" x 2 1/2" DC155635 Meter, TDS  range 0-9990 PPM Membrane - TW30-1812-24  Filmtec 24 GPD TFC 11.75"  RMSTD24T,Membrane, 25 GPD TFC  reverse osmosis membrane - standard size 1.75" X 11.75"
Membrane - 25 GPD TFC 11.75" RMSTD24T
IN STOCK
Your Price: $44.95
Sale Price: $38.00
EPM 20, Carbon Block Filter 20" in length and approximately 2 1/2" in diameter with a 5 Micron rating.
Used as either / both Pre-Filter or / and Post Filter
Meter measures the Total Dissolved Solids ( TDS ) in your water.
Use to determine if your Membrane is still working properly.
Offers Standard ( 0 - 999 ppm ) and High ( 1000 - 9990 ppm ) range for testing brackish water sources.
Membrane, Dow Filmtec � TW30-1812-24 24 GPD TFC RO reverse osmosis membrane - standard size 1.75" X 11.75"
Standard size membrane can be used as a replacement for most TFC model Reverse Osmosis.
Membrane, 50GPD TFC 11.75" TW30-1812-50 , TFM-50 Membrane - 36 GPD TFC 11.75"  RMSTD36T Water Shield Permeate Pump - ERP1000
Permeate Pump - ERP1000
IN STOCK
Your Price: $78.95
50 GPD (gallons per day) TFC style reverse osmosis membrane RO - Fits Standard Size Membrane Housing.
Tip to tip length 11.75 inches.
Membrane, 36 GPD TFC RO reverse osmosis membrane - standard size 1.75" X 11.75"
Standard size membrane can be used as a replacement for most TFC model Reverse Osmosis.
Permeate Pump - ERP1000
4 Stage  Reverse Osmosis 50 gpd TFC - CW5000, RO440, NRO4-50 Classic 3 Stage RO Watershield 36 gpd Microline TFC-335  Reverse Osmosis 50 GPD
RO Classic 3 Stage Watershield 36 gpd
IN STOCK
Your Price: $244.00
Microline TFC-335 Reverse Osmosis 50 GPD
IN STOCK
Your Price: $299.00
4 Stage TFC Reverse Osmosis Unit, 50 gallon per day production rate.
Pre-filter, Carbon Block filter, Membrane, and Activated Carbon Inline post-filter.
Watershield Classic 3 Stage Reverse Osmosis Drinking Water System.
Pre-filter, 36 gpd Membrane, Post-filter, Holding Tank, Faucet, and Installtion Kit ( plus Manual ).
Microline Reverse Osmosis ( STF35ANGNM or TFC-335 ), is now 35 gallon per day with a 50 gpd T.F. C. membrane ( S1229RS ), Carbon Block Prefilter ( S7028 ), GAC Post Filter ( S7025 ) with storage tank and all accessories to install.

Big Pump 3 Stage RO Watershield 36 gpd Membrane - TW30-4021 Filmtec 4 x 21 inches
RO Big Pump 3 Stage Watershield 36 gpd
IN STOCK
Your Price: $324.00
Watershield Super Big Pump 3 Stage Reverse Osmosis Drinking Water System.
Features Permeate booster pump for faster production of drinking water.
Membrane, Dow Filmtec TW30-4021 TFC RO reverse osmosis membrane - size 4" X 21"
Equilvalent Membrane will be shipped, not Filmtec.