While acidic water itself isn’t typically considered dangerous to drink, it is corrosive, which means that it’s much more likely to contain metals leached out of the walls of pipes and fixtures. These metals can cause health problems – ingesting too much copper, for example, can cause stomach pain and other gastrointestinal problems, and it may even lead to liver or kidney damage over time. You can often tell if your water has a low pH value because you’ll see blue or blue-green stains around your pipes and faucets from where the dissolved copper is being deposited; if you don’t have copper pipes, you’re unlikely to see such staining, however. In either case, it’s a good idea to run a simple pH test to see if you need some type of pH water filter.
Acidic Water Treatment Options
If you discover that your water is acid, meaning that the pH level is 6.5 or lower, you have several treatment options available. Which method is right for your home depends on how acidic your water is, your required flow rate, and if you want to neutralize the pH or simply prevent the water from corroding your pipes. A pH filter that adds a neutralizing agent, such as calcite or soda ash, can raise the pH and make the water less corrosive, while a polyphosphate injection system will help protect your pipes while not actually changing the water’s acidity.
Calcite Backwashing pH Water Filter Systems
One of the most affordable whole house treatment methods for acidic water is a calcite backwashing filter. This type of pH water filter system includes a tank that contains calcite, a form of calcium carbonate, or a blend of calcite and magnesium oxide. Water flows into your home from a well or municipal water system and into the tank. Calcium carbonate is commonly used to neutralize acids, and as the calcite is slowly dissolved into the acid water, it raises the pH.
Calcite and calcite-magnesium oxide blends are most effective when used to treat water with a pH of 5.5 or higher, which means that the water is only moderately acidic. This type of neutralizing pH filter is very simple to use and relatively affordable, although you will need to add more calcite every so often as it’s used up in the water treatment process. Because you’re adding calcium to the water, it will make your water harder; many people choose to add a water softener to this the of pH water filter system to avoid limescale deposits and other hard water problems.
This type of filter also needs to be backwashed every few days, which means that the water runs through the system backwards to help prevent the calcite media from being packed down too much and to resettle it correctly. It also takes time for the water to flow into the system and be treated completely.
Proportional pH Neutralization Systems
If your water is very acidic, meaning that it has a pH value of less than 5.5, you may need a proportional pH neutralizing system. This type of system injects a precisely calibrated dose of soda ash solution into your water, helping to ensure that the pH level of your water stays constant. When the water comes into your home, it first flows through a special water meter panel that determines the flow rate. This panel sends a signal to the injection pump, which delivers the correct amount of neutralizing solution to treat the amount of water that’s flowing into the system. The water then goes into a mixing tank so that the soda ash can be thoroughly mixed in, after which it’s distributed to your home.
Soda ash solution is very effective at raising the pH of water, and because it doesn’t contain calcium, it does not increase the water’s hardness level. Unlike a calcite pH water filter, this type of system does not need to be backwashed. You will need to refill the soda ash solution regularly, however. One of the biggest drawbacks of this type of system is that it tends to be much more expensive than a calcite backwashing pH filter.
Proportional Polyphosphate Injection Systems
To prevent acidic water from corroding pipes and leaving blue-green stains, a polyphosphate injection system can be used. Polyphosphates are naturally occurring compounds that deposit a protective layer on your pipes and fixtures. As a result, the water cannot leach metals out of your pipes. This type of pH water filter works much like the proportional pH neutralization system, but injects polyphosphate rather than soda ash; in addition, there is no mixing tank.
Polyphosphates are most effective on water that’s only mildly acidic, and they work best in water with a pH of 6.8 to 7.4. This type of system can also be quite expensive, often costing only slightly less than soda ash injection. It’s important to note as well that the pH level of the water will not be changed, only its effect on your pipes.