Chlorine is the prevailing choice for disinfection and biofouling control of drinking water, waste water, industrial water conditioning and swimming pool water. Too much chlorine can be as harmful as too little, so chlorine must be monitored carefully. High quantities of chlorine can cause health-related problems. The level of chlorine residual for drinking water must be checked regularly. Monitoring chlorine residual is essential for successful and efficient chlorination. A minimum free chlorine residual of 0.2 mg/L should be sufficient to maintain disinfection. Chlorine residual over 1.0 mg/L is too high and leaves a bad taste in the water.

Water hardness is caused almost entirely by calcium and magnesium ions. The amount of these ions and the amount of time the water stays in contact with them determines the water hardness level. Hard water causes scale formation in boilers, boiler feedwater heaters, feed lines, and economizers. In cooling water systems, scale will develop in heat exchange equipment and wherever water circulates and is exposed to a temperature change. Hard water also causes “soap curd” on fixtures, tile, dishes, and laundry. The water also has a low sudsing characteristic. Hard water aggravates dry skin conditions, takes the shine out of hair, and clings to skin. Water hardness is measured in grains per gallon. Hardness is measured as follows: Soft water is 0-1 GPG; Slightly hard water is 1-3.5 GPG; Moderately hard water is 3.5-7.0 GPG; Hard water is 7.0-10.5 GPG; Very hard water is 10.5 GPG & over.

Lead is a metal found in natural deposits as ores containing other elements. It is sometimes used in household plumbing materials or in water service lines used to bring water from the main to the home. The main source of lead in drinking water is from corrosion of household plumbing systems. Lead and its compounds are poisonous and accumulate in the bone structure when ingested in amounts exceeding the natural elimination rate of about 300 ug per day. Accumulation of significant amounts of lead in the body may cause severe and permanent brain damage, convulsions, and death. The EPA recommended limit for lead is 0.015 mg/L.

Manganese in water is a common, naturally occurring problem. It can also be introduced by industry. Manganese is usually found in combination with iron. It causes a bitter taste in water, and at concentrations above 0.05 mg/L, it causes dark scale in pipes and water heaters. High levels of manganese cause black staining of plumbing fixtures and laundry, and clogs up submersible pumps and pipes. The EPA recommended limit is 0.05 mg/L.

Nitrates and nitrites are nitrogen-oxygen chemical units which combines with various organic and inorganic compounds. The major sources of nitrates or nitrites in drinking water include runoff from fertilizer use, sewage, and erosion of natural deposits. Nitrogen is an important parameter to monitor. Excessive amounts of nitrate or nitrite in water can cause methemoglobinaemia (blue baby syndrome) which can potentially be fatal. These contaminants can also cause adult illness and produce spontaneous abortion in cows. The EPA recommended limit for nitrates is 10 mg/L and for nitrites is 1 mg/L.

Iron levels above 0.3 mg/L cause red-brown stains on sinks, tubs, and laundry. Iron levels over 1.0 mg/L result in a bitter taste in water. Iron is common in the Earth’s crust. As water moves through soil layers it dissolves iron causing it to seep into groundwater.

Iron bacteria are small microorganisms that live in water and soil and combine iron and oxygen creating a slime or biofilm that can clog pipes.

pH is the measure of the hydrogen ion content of a solution. It measures the acidity or alkalinity of water. pH is measured on a scale of 0-14. A pH of 7 is neutral and is considered desirable in most cases. A pH above 7 indicates an alkaline, or basic, water condition that is not usually harmful in residential applications. A pH below 7 indicates an acidic water condition. When pH drops below 6.5, the water is corrosive to metal pipes. This not only means that the pipes , faucets, etc. can be damaged by low pH water, but also that the water can contain high levels of copper, lead, or zinc that have corroded out of the plumbing system. For this reason it is always desirable to raise the pH of the water as close to 7 as possible. Blue-green staining of fixtures and laundry are characteristic of acidic water. Green stains on plumbing fixtures are indicative of copper pipes being corroded by low pH water.

Silica has the capacity to form scale deposits on surfaces it comes in contact with. Silica can cause hard water stains and cloudy glassware. Silica levels above 5 to 25 mg/L range are considered high.

Tannins are organic materials dissolved in the water. It is a product of decomposed plant material which occurs in natural waters. They can interfere with water softener filter resin beds and impart a distinctive yellow-brown color to the water. Tannins can also be associated with organically bound iron. Levels above 0.5 mg/L cause light brown or yellowish stains on laundry and fixtures. These levels can also affect the taste of foods and beverages.

Copper quantities ranging from 0.02 mg/L – 0.1 mg/L are toxic to some fish. Levels of copper over 1.3 mg/L are considered high by the EPA and cause blue-green stains on fixtures and may also cause health related problems. The most common cause of copper in well water is from corrosion. Acidic water can corrode and dissolve copper from your home’s pipes, fixtures, and plumbing.

Is a naturally occurring mineral that can cause a bitter taste and have a laxative effect in high amounts. Levels above 250 mg/L are considered high. Sulfate can contribute to plumbing issues and staining on clothes.

Are solid particles suspended in water that do not readily settle. It can affect water quality, making it unappealing to drink. Sources of Suspended solids include the well’s construction or old age and can allow sediment to enter the water source. Levels above 500 mg/L are considered high by the EPA.