Types of Water Filters
If you’ve read our blog about the common types of contaminates in Water in the Napa Valley, now you’re ready to read about the methods of filtering these interlopers from your water supply! Let’s get started.
Iron (red/brown staining) & Manganese (Dark Brown/Black staining
Iron & Manganese can be removed with several different methodologies. If these elements have not oxidized and are still in solution in the water with a pH that is less then 7, they can typically be removed with a water softener/ion exchange type filter. In this type of filter, sodium ions are put into the water and the iron/manganese ions can be removed. While simple and effective, this method means the water softener is not very efficient and may use lots of salt for regeneration.
If the iron is partially oxidized then addition of an oxidizer like chlorine or potassium permanganate to help finish the oxidation process and then a manganese greensand filter will remove the iron from the water.
Magnesium & Calcium (hard water that leaves white water spots)
Water Softeners excel at removing Magnesium and Calcium. They work by exchanging sodium/potassium ions into the water and taking the Magnesium and Calcium ions from the water. Water softeners require a bit of maintenance, but are reliable and straightforward and proven technology. Water Softener owners have the choice of using Sodium Chloride salt (cheap) or Potassium Chloride salt (expensive) as a regenerate for their water softener. People that need to minimize sodium in their diets should consider the potassium chloride salt for regeneration purposes.
There are many advertisements for “saltless” water softeners that are miraculous or employ new/amazing technologies. Don’t fall for the hype or the huge expense…they don’t work. Magnets that change the polarity of hard water don’t work, special sands, zapping the water with electricity…they just don’t work. Many of these companies have tried to have OPS sell their products, but when we ask for peer reviewed studies of the technologies or verifiable laboratory tests of these technologies-we never hear back from them. We’ve removed many of these expensive wonder filters purchased on the internet and replaced them with proven technology that works.
Silica (White haze which cannot be cleaned or removed and is actually caused by the microscopic silica particles bonding to the glass)
Silica is removed by two methodologies, both of which are expensive. The most straight forward methodology is Reverse Osmosis which requires the installation of the Reverse Osmosis unit, a storage tank to store the purified water in and a small booster pump to re pressurize the water from the storage tank. It is sometimes required to pretreat the water before the Reverse Osmosis filter to remove chlorine, iron or high levels of minerals that can cause the Reverse Osmosis membranes to fail prematurely. The second methodology uses an ion exchange filter that requires very acidic/basic solutions to regenerate. This second methodology is not recommended due to the safety and maintenance issues associated with the strong acids and bases.
Be careful of gimmick solutions for silica removal, these miracle filters abound and simply don’t work!
Low pH (low water pH means that the water is acidic and can corrode metal piping which can lead to red or green staining in fixtures)
Low pH is addressed in several fashions. The most common is called a pH neutralizing filter or a calcite filter. These filters pass the water by finely crushed limestone and this increases the pH. Small increases in pH can also be obtained by aerating water with a venturi or by putting it into a storage tank with an air bubbler. In cases where water pH is extremely low, sodium hydroxide can be carefully injected into the water to increase the pH to normal levels that do not corrode metal piping.
Bacteria (caused by a well influenced by surface water or a spring that is not tight enough to keep the bugs out).
Please check out our FAQ called How to Remove Pathogenic Organisms at this link to our FAQ page.
Arsenic (potentially dangerous at levels above 10 parts per billion, typically found in the Napa Valley from around St. Helena north to Calistoga)
Arsenic is often removed with filters that contain special filter medias that attract the Arsenic contaminants. These medias are extremely expensive and regular monitoring is important to ensure that the media is changed before the media is exhausted and needs to be replaced. It is also important to note that if you water contains iron along with the arsenic, that oxidation and filtration with Manganese Greensand will help reduce Arsenic Levels. Additionally, addition of ferric chloride can help with arsenic filtration.
Under-sink reverse osmosis units can also help remove or reduce arsenic levels and are the most economical method of ensuring drinking water is available at the kitchen sink. Not all under sink reverse osmosis units are the same, the specifications and capabilities of any proposed unit should be carefully reviewed to ensure it can remove any potential contaminates.
Hydrogen Sulfide (Smelly rotton egg odor)
The most effective method for removal of hydrogen sulfide is aeration. This is accomplished by putting the water in a storage tank and bubbling air or ozone through it. A secondary method involved injecting chlorine into the water to oxidize the hydrogen sulfide. The second method works, but if levels of hydrogen sulfide vary seasonally the rate of chlorine injecting must be adjusted to compensate for the changing levels.
Chlorine Removal
Perhaps you are on a city water supply or you treat your water for hydrogen sulfide with chlorine. There is a chlorine residual in the water that you can taste and smell. Using a Carbon filter will remove the excess chlorine taste and odor!
Whatever type of water quality challenges you face, Oakville Pump Service can help you find a solution that meets your needs and your budget. Give our team a call at (707) 944-2471 today.