water filters reverse osmosis membranes carbon block GAC CTS TFC comparisons

Large selection of replacement water filters, reverse osmosis membranes, testing kits and water filtration repair parts.  From one water filter or reverse osmosis membrane to case quantity discounts.
LOW PRICES and FAST SHIPPING SINCE 1999 !
99.5% Of All Items In Stock For Same Day Shipping!

Comparison Of Carbon Block Filters Versus GAC Filters (granular activated carbon)

GAC is crushed carbon held in a hard plastic housing.  Carbon Block is a solid carbon with a "net" around the outside.  Carbon Block is a superior design offering several advantages.

1.   Carbon Block will not "channel" like GAC can.  "Channeling" occurs when water forms a flow path between the crushed carbon particles in a GAC filter.   Channeling can allow water to pass untreated.  Carbon Block is pressed so tight that the water must pass "through" it.

2.   Carbon Block will not release carbon "fines" like GAC will.  "Fines" are very small pieces of crushed carbon.  GAC filters have a gray color to the first few gallons of water when first installed.  This is from the "fines".   It can continue to release "fines" even though they may not be obvious to the naked eye.  Carbon Block has no "fines".

3.  Carbon Block inhibits the growth of bacteria.  Bacteria can grow in the space between the carbon granules in a GAC filter.  Carbon Block does not have any space in the carbon for the bacteria to grow in.

4.   Carbon Block filters last longer than GAC filters, and are therefore a better value.  This is in addition to the superior performance of the Carbon Block design.

 

Comparison Of TFC Reverse Osmosis RO Membranes Versus CTA Membranes

It is very important to determine the style of reverse osmosis membrane your system uses.  It will either be a CTA membrane or a TFC style membrane.  CTA membranes are made to allow contact with chlorine in the water.  TFC membranes are chlorine "intolerant" and cannot come into contact with chlorine.  The chlorine will destroy a TFC membrane.   Therefore TFC systems are ALWAYS equipped with a carbon pre-filter that removes the chlorine.  TFC can be utilized on ANY tap water system, well or city.  CTA or Cellulose Tri-Acetate membrane is an organic membrane.   CTA membranes typically use a sediment prefilter and pass the chlorinated water into the tank.  The carbon post filter then removes the chlorine.  TFC or Thin Film Composite membrane is a synthetic membrane that has a removal percentage between 94-99%.  A TFC membrane uses a carbon pre filter before the membrane to remove the chlorine and then another carbon filter after the membrane to "polish" the water just before dispensing.  TFC membranes have a higher rejection rate of many chemicals than CTA membranes and the extra carbon filter additionally removes more contaminants than the single carbon filter used in CTA systems.  TFC membranes will typically last 3 to 5 years.  CTA membranes typically last 18 to 24 months.  CTA has a typical removal percentage of 86-94%.  Since the CTA is an organic membrane, it needs chlorine to protect itself from damaging molds and bacteria. The CTA membrane MUST be run with chlorinated water and cannot be run on non-chlorinated water systems (wells).  The only way to know if your membrane is working correctly is to measure and compare the TDS (total dissolved solids) in the incoming feed water and the product drinking water.  To do this you will need a TDS Tester.

Comparison Of Five Stage Versus Four Stage Reverse Osmosis RO Systems

The difference between a four stage reverse osmosis RO system and a five stage system in most industrialized countries such as the USA is typically the addition of a second carbon pre filter.  In some countries where the incoming water is not well treated or has high turbidity the additional pre filter may be a sediment filter.  Most five stage systems come with the additional carbon filter.  The additional carbon filter is usually a GAC filter followed by a carbon block pre filter.  Click here to see a comparison of the two.  The additional carbon pre filter assures a more complete removal of many contaminants.  It also helps assure the removal of the chlorine which can damage a high quality TFC RO membrane.

Comparison Of Quick Change Replacement Water Filters Versus Standard Replacement Cartridges

Quick change filters are self contained.  They usually "screw" into the filter head.  When replaced you simply unscrew them and discard the entire one piece filter.  Standard replacement cartridges are filters that fit inside of a filter "housing".  To replace, you unscrew the housing and remove the cartridge inside.  Then clean the housing and install a new cartridge and screw the housing back onto the "head".  The advantage of the Quick Change filters are that they are faster and easier to change.  Since you are throwing away the housing there is no need to sanitize it before installing the new filter.  The advantage of the standard style filter cartridges is that they are less expensive and more readily available. 

Be sure to check our Parts Department for important parts such as TDS Testers, Replacement Tanks, O-rings , Housing Wrenches and more parts for your reverse osmosis pure water filtration system.