Drinking Water FAQ

Read below to answer any questions you may have about your drinking water.

Protect Your Health

What is Cryptosporidiosis?

Cryptosporidiosis is a disease caused by the parasite cryptosporidium parvum. It was not known to cause disease in humans until as late as 1976. In 1993, over 400,000 people in Milwaukee, Wisconsin became ill after drinking water contaminated with the parasite. Few people had heard of crytosporidiosis, or the single-celled protozoan that causes it.

Since the Milwaukee outbreak, concern over the safety of drinking water in the United States has increased. Attention has been focused on determining and reducing the risk for cryptosporidiosis from community and municipal water supplies.

Filters: what can they do?

Many types of filters are available today. They are grouped by the method they use to filter water. Filters that fit on the end of your kitchen faucet or bathroom spigot use two basic types of filtration: a filter 'pad' catches the large (usually over 25 micron in size) particles or 'chunks' , and a small amount of carbon will absorb organics and/or chlorine. The main problem here is the flow rates at which they are expected to work. If you purchase this type of filter, make sure it has a way of limiting the rate at which water passes through it.

Next is the cartridge-type filter. Most common are the 10 1/2 or 20 inch long filters. This type of filter will usually have a removable housing, into which different types of "elements" can be placed. A sediment filter cartridge element can be manufactured to remove certain sized particles and larger. Most elements for home use will indicate 30 or 50 microns and larger removal. More expensive elements, usually for industrial use, may indicate a particle size (in microns) and add the words "Absolute" after it. This means that very few particles larger than 5 microns will pass through the filter. The regular filter may say 25 microns, meaning that *most* of the particles 25 microns and larger will be caught by the filter. As the filters are used, the debris in the water will collect on the surface of the filter and become a part of the filter. Smaller particles are trapped, they build up, and the flow rate through the filter slowly diminishes. This slowing of water flow can be a problem if you have appliances in your home that use water. Regular changing of the filter element is very important for this dilemma. Elements for these filters can be: carbon (block or granular, or powdered), they can be manufactured for use in hot water, they can be ceramic, pleated or many other configurations. Some manufacturers are mixing a small amount of silver into the carbon to help prevent any bacteria growth in them. This has yet to be a proven methodology. In fact, make sure that such a filter doesn't give off more silver than is allowed. They should be rinsed thoroughly prior to use, and especially after a prolonged period of non-use. Remember, all filters, (especially carbon), trap organics that bacteria feed on. As the water sits without moving, bacteria can multiply rapidly. Always change the elements on a regular, frequent basis.

Selective Resins

Some small filters now contain resins that only remove specific things from the water such as nitrates, fluoride, or lead. Technology is rapidly changing in this area. If you have a need for such a device, you should ask for supporting test results from an independent testing lab to verify that the unit will perform as advertised. Many states now have legislation that requires such data be provided to you prior to purchase.


Used mainly in labs, manufacturing processes, or for serious aquarium owners, DI filters are actually more complex than a filter. True filters, unlike the selective resin and DI units, work on a mechanical basis. They just 'catch' the particles that are too large to fit through the spaces between the filter media. DI works by ion exchange, just like a water softener. Just as a water softener exchanges sodium for hardness minerals, a DI unit will have two types of resin in it: Cation and Anion. The Cation resin (like in a water softener) removes the ions with a positive charge, while the Anion resin removes those ions with a negative charge. Instead of using salt as a regenerate, acid and caustic are used. Some small DI cartridges are sold as "throw-aways", others can be returned for regeneration and reuse. These small units can treat only small amounts of raw, city water. Usually, it is much more economical to pre-treat the water feeding a DI system with reverse osmosis water.


One of the oldest methods for cleaning water is distillation. Simply put, boil the water, catch the steam, and condense it back into water. The minerals stay behind in the boiling chamber, and only *pure* water ends up in your container. It is very important to perform preventative maintenance on your still. Otherwise, very poor results will occur. Distillation will kill bacteria, viruses, and cysts. It also removes heavy metals, organics, radionuclide, inorganic and particulates if properly maintained. Be aware of VOC's (volatile organic chemicals). These chemicals have a lower boiling point than water. They can vaporize and mix with the steam, carrying over into the product water. Some stills today have a volatile gas vent -- a small hole at the top of the condensing coil that allows the venting of such substances. Many distillers have a carbon filter to "polish" the product water before use, and to remove any VOC's that may carry over. The energy used to treat a gallon of water is usually about 3,000 watts, or about 25 cents per gallon (average) in the US. This treatment method requires that you 'plan ahead' and make and store water for use. The more elaborate units will make and store water automatically,.

Reverse Osmosis

This is a process that is often described as filtration, but it is far more complex than that. Reverse osmosis takes water with nutrients in it, and applies pressure to the water against a special membrane. The membrane "filters" out the nutrients, and the result is clean water. Depending on the membrane design, and the material it is made from, the amount of TDS (total dissolved solids) reduction will range from 80 to over 95 per cent.

If using an RO system for home use, be sure to have: a sediment pre-filter, a carbon pre-filter, membrane, storage tank, and post- carbon filter. Some of these filters may be combined into one. For instance, the pre-filter may be both particulate and carbon. The newer membranes are made to recover more, and they can have a shut-off device that stops all water flow when the storage tank is full. Actual recovery rate depends on the TDS in the feed water, and what the TDS is composed of. Temperature and pressure also have an effect on the amount of product water you can make in a given period. Remember, all reverse osmosis units are normally rated using a feed water temperature of 77 degrees F -- is your feed water temperature that high?

What is the best water for coffee?

After visiting with many every day coffee drinkers, the following information was gathered and used as a basis for recommending the "perfect water" for coffee.

  • -All oxidants removed.
  • -All organics removed (THM's, insecticides, pesticides, etc...)
  • -TDS (total dissolved solids) from 60 to 100 PPM (parts per million).
  • -Hardness of about 3-4 grains per gallon (51.3 to 68.4 PPM).
  • -Low sodium water, i.e., less than 10mg/L.
  • -pH depends on the coffee bean you are using, plus the method of extraction.
  • -Iron, manganese, and cooper should be gone, or less than 0.02 PPM

Please contact us for more information on drinking water treatments.

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