Frequently Asked Questions        


Will my family be deprived of minerals necessary to good health in drinking water softened by the ion exchange process?

Is soft water safe for tropical fish?
Does soft water affect the operation of a humidifier?

Can an ion exchange softener effect the removal of radioactive contaminants from water?

Should softened water be used for watering house plants or for sprinkling the garden or lawn?

Will soft water produce clearer ice cubes?
Does a water softener have any harmful effect on a septic tank?
Is the sodium in softened water harmful to people on restrictive salt diets?
What general procedures should be used with household dishwashers?
Can softened water be used for a steam iron?
How much soap or detergent should be used in softened water?
Can pink water stains be caused by micro-organisms?

Will my family be deprived of minerals necessary to good health in
drinking water softened by the ion exchange process?


No.  The human body gains the minerals necessary to good health primarily through eating foods, not through drinking water.  The body may absorb or use the minerals in water but, in most cases, the amount would not be significant. In order for a person to obtain sufficient minerals from water, it would be necessary to drink many gallons daily.  In general, neither a water with a high  mineral content, nor a fully softened water, could be considered a significant source of minerals.  In contrast, one glass of milk provides the mineral equivalent of multiple gallons of ordinary well water.  (Cow’s milk contains about 8,000 milligrams per liter of dissolved minerals.)

Is soft water safe for tropical fish?


Yes, soft water is satisfactory for most tropical fish.  According to several authorities, both fully soft water and municipally softened water would have no undesirable or toxic effect for use in an aquarium. When making the change from hard to soft water, it is necessary to make the substitution on a gradual stepwise basis of new water for old.  This follows the basic pattern in regard to any change in the environment for tropical fish. This applies to temperature, pH of water, food, as well as to hardness. Drastic changes, of course, would constitute a shock to the delicate systems of such fish and could result in fatalities.  Preferably replace about one-fourth of the aquarium water at weekly intervals with soft water.  Eventually, the aquarium will have a supply consisting of essentially soft water, and the fish  will suffer no ill effects as a result of the change.

 Note:  While soft water is an improvement in that it reduces the clouding and scaling of the glass panels of an aquarium, it does not, of itself, necessarily provide a suitable environment for the breeding of tropical fish.  Authorities indicate that water of low dissolved solids and pH control may be more desirable for breeding, though this depends on the      species.  Since total dissolved solids content of a softened water is the same as that of the untreated raw water, a supply with a lower dissolved solids content must be gained in some other way.  Blending of softened water with reverse osmosis or distilled water may produce the conditions conducive to breeding.

Does soft water affect the operation of a humidifier?


Yes.  Soft water provides for easier maintenance of a humidifier.  When hard water is evaporated, the mineral residue consists of a hard scale which  normally requires some drastic treatment (such as chipping or acid) for its  removal.  When soft water is used, the residue is commonly called soft and  can usually be removed by flushing the unit with water or going over the  surface with a brush.

 A point to remember:  Softening water does not reduce the total amount of  minerals present; ion  exchange softening merely converts the calcium and  magnesium minerals to sodium minerals.  The humidifier most common in  homes has an open pan, a small tube connected to a water source, and float  valve.  When water evaporates, the float valve opens to permit make-up  water to flow into the pan.  Sooner or later this type of unit fills with minerals  deposited by the inflowing water.

Many humidifiers today automatically accomplish periodic flushing with soft water to keep the mineral concentration down, and the unit operating satisfactorily.  Soft water minerals will flush or rinse away much easier than will hard water mineral deposits.

Note:  A modification of the pan-type humidifier uses wicks to increase the surface of water exposed to the air and thus increase the evaporation rate.  The wicks in such humidifiers are particularly susceptible to clogging due to scale.  When this occurs, the wicks must be replaced.  When soft water is used, however, the mineral deposit can be re-dissolved by soaking the wicks in fresh soft water. There is also another type of humidifier that physically sprays a fine mist of water into the air.  If minerals are present in the water, they settle out of the air as a fine powder.  Depending on the mineral concentration, the amount of water evaporated, and the use of the humidified air, a wide variety of problems may be encountered. In homes, a few grains of minerals per gallon of water may be tolerated, but higher concentrations may lead to large quantities of fine dust throughout the home.  Again, the severity of the problem depends upon the amount of water evaporated.  In industries, where the fine dust may act as an abrasive in machinery and equipment, the problem may be much more severe.  Thus, the best water for such humidifiers is water which is free of all dissolved minerals, such as de-mineralized water.


Can an ion exchange softener effect the removal of radioactive contaminants from water?


Yes, a water softener will effectively remove from 80 to 97 percent of the  cationic radioactive substances such as radium found in water.  Water softening will not, however, remove radioactive radon gas or anionic radioactive species (e.g., uranium). Radioactive radium, barium, and strontium, for example, are much preferred by ion exchange water softening resins over the water hardness cations, calcium and magnesium.  Therefore, one can always be confident that so long as a water softener is softening water, it is even more effectively removing these cationic radioactive isotopes.

The discharge of water softener regeneration wastes results in the same course for the radioactive constituents in the sewer system as if the softener was not used to protect the drinking water.  They usually end up the sewage sludge and at no higher concentration than would occur without ion exchange softening. Reverse osmosis and distillation will also substantially remove both radioactive cations and anions with continuous concentrated waste disposal. Because some radioactive substances are anionic, while others are cationic, demineralization units employing strongly acidic action resin and a strong base anion resin can be utilized to remove both species types. Small “throw-away” de-mineralizers are available for emergency needs.  Such units offer a very satisfactory solution to this problem, but should be used following reverse osmosis. Activated carbon and/or deaeration are effective means to reduce radon gas from a water supply.

Should softened water be used for watering house plants or for sprinkling the garden or lawn?


Where the amount of hardness minerals in the water is only moderate (less than10 gpg), it is doubtful whether the sodium concentration would be sufficient to be a serious hazard to plants.  Most house plants require specific soil conditions for healthy growth.  Many thrive best in slightly acid soils.  If there is a high hardness concentration in the water being softened, the necessarily higher sodium concentration of the soft water may be harmful to plants.

For outside sprinkling purposes, the use of softened water, for economy reasons, is not recommended unless necessary to prevent iron stains on buildings and concrete.  Again, where the concentration of hardness minerals is heavy, the sodium salts replacing them might retard growth and might be sufficient to kill the grass.

Note:  Where rainfall is rare, sodium accumulation is apt to be greatest. Heavy rain “rinses” the earth.

Will soft water produce clearer ice cubes?


Actually removing calcium and magnesium from the water has little effect on the quality of ice prepared in the home.  Here again, the reason is that softening the water does not reduce the total mineral concentration.  To the extent that a softener removes sediment iron and manganese, for example, from water,  this would help to produce at least cleaner ice.  Filters, of course, can be helpful in removing iron, turbidity, tastes and odors from water used for ice making.  De-mineralized water such as from reverse osmosis, distillation, or deionization is most ideal for ice making for all types. The use of polyphosphates is an economical method of treating water used in typical restaurant ice making units.  The polyphosphates keep the minerals in the water dispersed and, in this way, minimize the cloudy appearance of ice cubes.

If fed in proper concentrations, polyphosphates also control scale formations and corrosion in the ice cube machine.  Approximately 5 ppm are recommended for scale prevention and 10 ppm for both scale prevention and corrosion control.

Note:  Total minerals must be below 10 grains per gallon for first quality ice.  Large commercial ice producers have found that water containing more than 20 gpg of minerals causes difficulties in the freezing process.  Further, water with such a mineral content may make a brittle ice of poor quality. Large commercial ice plants use such processes as    osmosis, lime softening, alkalinity reduction, filtration and/or deaeration to produce the high quality of water needed for quickly freezing quality ice with a minimum of labor and        expense.  Reverse osmosis filter units are available in sizes small enough to be used in restaurants, homes, and other small installations, but the other processes are too large for these applications.

Does a water softener have any harmful effect on a septic tank?


Several studies have been made to determine the exact nature of water softener recharge waste effluents and their effects on private sewage disposal systems.  These studies evaluated three major areas, all dealing with the effect of effluents developed during the recharge of household water softeners. First, it was important to study the effect of dissolved salts in softener recharge effluents on biological action in septic tank systems.  These studies demonstrated that recharge effluent from water softeners had no deleterious effect on the biological action in a septic tank and that the recharge waste effluents may    actually stimulate biological action.

Second, it was felt important to assess the hydraulic effect of the volume of water softener waste water.  These studies demonstrated that the volume of recharge effluent from a water softener is less than that of present day automatic clothes washers.  The amount of waste effluent developed by a typical household water softener during recharge is about 50 gallons containing calcium, magnesium, and sodium chlorides.  The frequency of recharge is dependent on water hardness, water usage, and recharge salt dosage.

The last area of study concerned the effect of softener recharge effluents on soil percolation in septic system drain fields.  This portion of the study is important since much of the literature on irrigation contains references to the adverse effects of high sodium water on soil structure and permeability, particularly in clay-type soils.  The study concluded that there was an important difference between water softener effluents and sodium effluents, which has an important bearing on soil percolation and permeability.

The important difference is that water softener effluents contain significant amounts of calcium and magnesium and thus are not really sodium effluents alone.  Calcium and magnesium counteract the effect of sodium and help maintain and sustain soil permeability, even in susceptible clay-type soils.  Thus, it appears that water softener recharge effluent brine will not affect biological digestion, hydraulic load, or leach field permeability in a septic tank system.

However, if the leach field is composed of swelling clays, permeability will be reduced regardless of the presence of water softener effluent.  Moreover, calcium and magnesium contained in recharge effluents actually increased soil permeability. Salts in the waste effluent from recharge of water softeners created no hydraulic conductivity or percolation problems in a properly designed septic tank seepage field.  In fact, it was found that soil percolation was increased by water softener recharge effluents, as compared to soil receiving household sewage effluents without the addition of effluents from the recharge of water softeners.  In other words, lower hydraulic conductivity (HC) might result if regeneration or recharge wastes from water softeners were not allowed to enter the septic tank seepage field.  In this case, the beneficial effects of calcium and magnesium would be lost.  This would occur if the regeneration wastes were not discharged to the septic system, but to a dry well, roadside ditch, or other point.

One study was conducted by soil scientists at the University of Wisconsin and dealt solely with anaerobic septic tank systems.  The other study, conducted by the National Sanitation Foundation, dealt solely with aerobic tank systems. Conclusions reached in this study were as follows:  Water softener regeneration wastes demonstrated no adverse effects on home aerobic waste water treatment plant performance, even when stressed by loading at a use rate simulating ten persons (twice the average use rate).  There was no difference in performance between days in which the plant received regeneration wastes and days in which it did not.

Is the sodium in softened water harmful to people on restrictive salt diets?


The amounts of sodium in softened water are miniscule compared to other normal dietary sources of sodium.  In fact, ion exchange softening of water with even 75 grains per gallon of total water hardness would add less sodium to the drinking water than is allowed in beverages meeting the U.S. Food and Drug Administration regulations for “Low Sodium” labeling.

In establishing a salt-free diet for patients, physicians should not overlook the fact that even hard water may contain appreciable amounts of sodium.  To determine the amount, a complete analysis of the water is necessary.

How can the sodium content of a softened water be determined in terms of milligrams of sodium?

1. First, determine the sodium content of the natural water.  Multiply the water’s sodium content in grains per gallon expressed as calcium carbonate, by 7.86.  This will give you the sodium content of the water in milligrams per liter of water (gpg CaCO3 X 17.118 mg/L/gpg X 22.99 Na+/50.0436 CaCO3  = 7.86).

2. Next, determine the additional sodium content of water as the result of ion exchange softening.  Here, multiply the total hardness of the water in grains per gallon, expressed as calcium carbonate, by 7.86.

3.  A simple addition of the results of both steps No. 1 and 2 will give the sodium content of the softened water in milligrams of sodium per liter. One to two liters (1 liter equals 1.057 quarts) is commonly accepted as normal daily water consumption.

Actually, the amount of sodium present in softened water is small when compared to the sodium present in foods.

The Food                                Amount                      Milligrams of Sodium


  Milk                                       2 cups                                    244

  Eggs                                       1                                              59

  Meat                                       4 ounces                                  76

  Bread                                     3 slices                                   342

  Cereal                                    1 cup                                      256

  Potatoes                                 1 medium                                  5

  Vegetables (peas)                   3 ounces                                 402

  Vegetables (cauliflower)          3 servings                                15

  Fruit (apple)                               1                                          2

  Fruit (grapefruit)                        ˝                                          1


                           Total milligrams of sodium                          1,405

It is important to note that about 2/3 of the daily water intake of the individual  is through food and only about 1/3 from water itself.


What general procedures should be used with household  dishwashers?


In any case, the instructions of the dishwasher manufacturer should be followed.  However, these may be supplemented with the following general considerations.

Avoid the use of sudsing soaps or synthetic detergents as the suds which develop can “muffle” the spray action used in most dishwashers to provide scrubbing action.  A number of washing compounds are on the market which have been specifically formulated for dishwashers. The materials do not generally contain any soap -- they depend upon the presence of greases and oils on the dishes to produce a cleaning solution.

Even with the use of soft water, spotting of dishes is sometimes reported.  In some cases, the cause may be traced to the use of too much washing compound.  In other cases, the dishwasher is loaded too heavily, and improper cleaning occurs. Another common cause of spotting is too rapid trying.  Ideally, the dishes should first be allowed to drain completely in a humid atmosphere so that the water with its minerals runs off, rather than evaporates.  In some cases, the water temperature is too high, and the water evaporates rather than drains. In other cases, the dishwasher lid opens at the end of the cycle and allows cool air to contact the utensils.  This, too, results in rapid evaporation.

Depending upon the construction of the dishwasher, it may be possible to adjust one or both of these factors to significantly improve results.

Can softened water be used for a steam iron?


Neither hard nor soft water should be used with a steam iron. Distilled water, or water treated by reserve osmosis, is acceptable for use over a period of time.  Bear in mind that the softening of water does not remove the minerals, but soft water minerals can be more easily rinsed from the iron.

How much soap or detergent should be used in softened water?


When first using softened water for household cleaning chores, it is best to use as little soap as possible.  If necessary, the homeowner can gradually increase the quantity to produce the results desired.

The habit of using far too much soap is not easily broken.  Therefore, anyone contacting the customer should stress the coffee measure as being adequate, rather than the cup or more that may have been necessary prior to the installation of a water softener.

Can pink water stains be caused by micro-organisms?


Yes.  Homeowners can experience an unusual problem of a pinkish substance on bathroom fixtures that is very persistent and appears in the shower, the sink, and especially along the waterline of toilet bowls.

 This pink residue is less likely a problem associated with water quality than with naturally occurring airborne bacteria.  The bacteria produces a pinkish film, and sometimes a dark gray film, on surfaces that are regularly moist, including toilet bowls, showerheads, sink    drains, and tiles.  The problem also more commonly occurs in humid regions of the country. To determine the exact species of bacteria would require lengthy and costly laboratory testing, and for those reasons most homeowners are reluctant to have the tests performed.  Although the exact species of bacteria is not known, most experts have concluded that this pink staining is most likely from the bacteria Serratia marcescens. 

Members of the Serratia genus are essentially harmless organisms that produce a characteristic red pigment.  These bacteria thrive on moisture, dust, and phosphates and are widely distributed, having been found naturally in soil, food, and also in animals.  The conditions for the survival of Serratia marcescens are minimal, and the bacteria may even feed upon itself in the absence of other nutrients.

Many times, the pinkish film appears during and after new construction or remodeling activities.  The dirt and dust stirred up from the work probably contains Serratia bacteria.  Once airborne, the bacteria seek moist environments to proliferate.  Some people have   even noted the pink residue in their pet’s water bowl.  It causes no apparent harm and can be easily cleaned off.  Others have indicated that their experience with this nuisance occurs during a time of year that their windows are open for the majority of the day.  These air-   borne bacteria can come from any number of naturally occurring sources.

The best solution to keeping fixture, sink, and bathroom surfaces free from this bacterial film is continual cleaning.  Chlorine bleach can be periodically stirred into the toilet tank and flushed into the bowl itself.  As the tank refills, more bleach can be added.  Three to five tablespoons of fresh bleach should be all that is necessary.  A toilet cake that contains a disinfectant can keep a residual in the water at all times.  The porous walls of a toilet tank can harbor many opportunistic organisms.

Cleaning and flushing with chlorine will not necessarily eliminate the problem, but will help to control these bacteria.  Keep bathtubs and sinks wiped down and dry to avoid this problem.  Using a cleaning solution that contains chlorine will help curtail the onset of the bacteria.                

                                    SIZE ANALOGY COMPARISONS

Sewing Needle Diameter                   600           Microns

Razor Blade Thickness                      300           Microns

Human Hair Diameter                         80           Microns

Smallest Visible Particle                     40           Microns

Aluminum Foil                                    18           Microns   ----   Particle Filtration

Red  Blood  Cell                                  8           Microns

Giarda Cyst                                      7-8           Microns

UMF  Prefilter                                     5           Microns

Cryptospordium Cyst                       -3           Microns

Bacteria                                                .5           Microns   ----   Micro Filtration

Polio Virus                                         .03           Microns   ----   Ultra Filtration

Virus                                                 .001           Microns

R.O. Membrane                               .0001          Microns   ----   Hyper Filtration


R.O. rejects up to 99% of chloride ions in water.  If a chloride ion were the size of a golf ball, a virus would be the size of a 40 ft. room and a bacteria would be the size of WRI’s building 800 ft. across. If 1 sq. ft. of membrane was the size of the Pacific Ocean, a R.O. membrane pore would be the size of a dime.

Water Flow Analogy:

The membrane element works like a manila envelope -- sealed on three sides and open on one end.  The tap water flows across the outside of the envelope and some of the water is forced through the membrane to the inside of the envelope.  Once inside, there is only one place to go -- to the open end of the envelope where a tube is attached and collects the purified drinking water.

Osmosis and Reverse Osmosis Description:

Osmosis occurs naturally in our bodies.  Each cell is surrounded by a membrane which allows pure water to flow in and out, but keeps everything else inside.  Pure water will naturally be drawn inside the cell until it reaches a certain pressure inside.  By pushing on the cell, some pure water can be forced out.  This is reverse osmosis -- reversing a naturally occurring phenomenon to make pure water.




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