09/27/2021 | Aquaculture | 9 MINUTE READ

What is Acidic Water and What Are the Primary Treatment Options?

rainwater acidity

Regardless of the source that a sample of water comes from, water can be acidic, alkaline, or neutral. Acidic water occurs when the water’s pH drops below 7.0. In most cases, the water becomes acidic because of the introduction of different contaminants to the water. These contaminants can include everything from agricultural chemicals to microorganisms. Once the water’s pH goes above 7.0, the water is considered to be alkaline. The ideal pH levels for drinking water are between 6.5-8.5.

Since water becomes more acidic as contaminants are introduced to it, you should be careful and avoid ever drinking acidic water. The types of contaminants that are present in the water can dictate what occurs if you drink acidic water. For instance, it’s possible that the water contains a heightened amount of bacteria and viruses, which could lead to serious health problems if you attempt to drink the water in question.

Along with health problems, acidic water can create issues with water fixtures and industrial machinery in the form of corrosion. Keep in mind, however, that alkaline water can also be damaging to industrial machinery. For instance, an increase in the concentration of magnesium and calcium can cause scale deposits to develop in industrial systems and machinery, which will invariably create additional problems with the system’s efficiency and condition. If scale deposits aren’t eliminated quickly, the machinery could malfunction altogether.

Because of the myriad issues that can be caused by acidic water, it’s important that you take steps to measure the pH levels of water whenever possible. Identifying the pH of a water sample is straightforward and can be accomplished with a basic pH sensor or test kit. These results from these sensors and test kits are easy to read and will help you determine what your next steps should be. If you need to maintain a certain pH for industrial processes, your next step may involve water treatment. This article takes an in-depth look at acidic water and how to effectively treat it.

Causes of Acidic Water

There are numerous causes for acidic water, many of which are natural processes. Whenever it rains, the rainwater mixes with soil and can seep into well water. Rainwater is considered to be highly acidic. As water evaporates, all of the minerals that are present in the rainwater remain behind. The acidic rainwater will then seep into the ground and eventually reach the well water. While the water is going through the soil, it typically picks up minerals along the way, which can increase the water’s pH to the point that the water would be considered alkaline.

However, it’s also possible for the rainwater to get through the soil and into well water without picking up a substantial sum of minerals, which would cause the water’s pH to be very low and for the water itself to be acidic. In this situation, the water would need to be treated before you could drink it. The evaporation of rainwater that naturally occurs is similar to the distillation process that’s used to purify water. During the water distillation process, the water is evaporated to properly separate it from the contaminants within. The only issue is that the minerals that are discarded during evaporation can be necessary to keep the water’s pH levels from dropping substantially.

rainwater acidity

Acidic Water’s Effect on Plumbing

As mentioned previously, acidic water can create significant problems with industrial equipment and plumbing systems. While alkaline water can be harmful because it promotes the development of scale deposits, acidic water is known to be highly corrosive. If acidic water is traveling through your household’s plumbing system, the pipes could be damaged beyond repair.

Because of how corrosive acidic water can be, the copper within your pipes will start to dissolve. You may begin to notice that the drains in your sinks and bathtub have blue-green stains around them. This kind of discoloration occurs when copper dissolves. If you don’t quickly tend to the problem, pinhole leaks within the piping may start to develop, which could lead to substantial water damage throughout your home.

Keep in mind that water damage can cost thousands of dollars. If you need to replace the entire plumbing system in your home, this may cost upwards of 20% of your home’s current value, which is an ample sum of money. In the event that the plumbing system around your home uses plastic water tubing in the form of PVC or PEX, acidic water may not cause as much damage as it would to copper pipes.

Acidic water can also lead to severe damage in water heaters and other hot water appliances. When the water increases in temperature, the water’s corrosive properties will become more potent, which makes it more likely that your water heater will malfunction. Another issue that occurs when acidic water enters a plumbing system involves leaching.

When acidic water is sent through your home’s metal pipes, the metal ions will be leached from the pipes, which means that these ions will enter the water supply. When this occurs, your water may contain exceedingly high levels of lead, iron, copper, zinc, and manganese. If you happen to drink water that contains a high concentration of heavy metals, this could be toxic to you. The presence of copper and iron in the water will leave stains around your plumbing fixtures.

Health Risks of Acidic Water

As touched upon previously, there are several notable health risks that come with drinking acidic water. In the event that heavy metals have been leached from your home’s plumbing system, the water could be particularly dangerous to drink. If the water contains high amounts of copper, you may start to experience such severe health complications as neurological damage, kidney stones, gallstones, kidney failure, and liver failure.

Lead is also a dangerous substance to consume that’s especially problematic for children. Because a child’s body is growing at an accelerated rate when compared to an adult, children absorb contaminants more than adults do. High lead exposure can create memory problems, seizures, stunted development, and cognitive impairment. As for adults, exposure to lead may cause a stroke, cancer, kidney disease, or high blood pressure.

Even though alkaline water is generally healthier than acidic water, there are still some problems with alkaline water that you should be aware of before you drink it. For instance, your body’s normal pH could be thrown off balance if you drink too much alkaline water, which could result in the development of metabolic alkalosis. This condition can produce symptoms like:

-Hand tremors
-Muscle twitching

If you’re testing the pH of the water in your home, keep in mind that pH readings below 7.0 are known to be acidic. On the other hand, pH readings above 7.0 are alkaline.

Best Ways to Treat Acidic Water

There are several methods available to you when you want to treat acidic water, which include everything from calcite to magnesium oxide.


Calcite is the most common treatment for acidic water and is available in the form of a whole-house acid neutralizer. These systems use calcite to increase the water’s pH before the water can enter and damage your household’s plumbing. Calcite is a type of substance that’s created from crushed white marble and is very high in calcium. This substance has high alkalinity, which means that its pH is high. If you purchase an acid neutralizer tank, the system should be positioned at your home’s entry point for water.

When water comes into contact with the calcite in the system tanks, the calcite will dissolve, which ensures that the water’s pH rises. Along with being inexpensive, calcite is a great treatment for acidic water because it can only raise the water’s pH to neutral levels of 7.0. As such, you don’t run the risk of making your water too alkaline. The main limitation behind calcite is the fact that it must be in contact with water for a lengthy period of time. The self-limiting nature of calcite also means that it can only increase the water’s pH by around one point. Because of this, the calcite treatment method is ideal if pH levels are around 6.0.

Magnesium Oxide

Magnesium oxide is a great solution for acidic water if your water has a pH level of around 5.5. This solution works by neutralizing the carbon dioxide that’s present in your water. If you combine magnesium oxide with calcite, you can increase your water’s pH levels by 1.5. The main limitation with magnesium oxide is that it’s easy to substantially increase the water’s pH if you happen to add too much of the substance to your water. Try to use a blend of 10-20% magnesium oxide and 80-90% calcite. Keep in mind that too much magnesium oxide could lead to the water having a laxative effect when consumed.

Soda Ash and Caustic Soda

If the pH level in your water happens to be between 4.5-5.0, you may find it difficult to substantially increase the water’s pH. For instance, using an acid neutralizer tank won’t be effective for acidic water with a pH level of 4.5 or so. Instead, it’s highly recommended that you use a chemical injection system to increase the water’s pH. The chemical that’s used in this system is known as soda ash.

A chemical injection system uses a peristaltic pump to properly inject the water with dissolved soda ash, after which it well be sent through your home to improve the water’s pH. Keep in mind that these systems have high maintenance requirements, which is the main downside to using one of them. However, a chemical injection system may be necessary if the water in your home is too acidic.

Even though acidic water can be highly damaging to your health as well as your home’s plumbing system, there are several effective ways to reduce the water’s acidity and make sure that your health and home are protected.

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Posted by Sensorex on September 27, 2021

Sensorex is a global leader in the design and manufacture of quality sensors for water quality and process applications. The company offers more than 2000 sensor packages for pH, ORP, conductivity, dissolved oxygen, free chlorine, chlorine dioxide, UV transmittance and other specialty measurements, as well as a full line of sensor accessories and transmitters. Its expert technical support engineers solve analytical sensor challenges with custom designs and off the shelf products.

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