A technical paper by Olympian Water Testing specialists
Table of Contents
The concept of pH
pH is a very simple concept in water chemistry that can be used in many different ways.In this article, we’ll talk about pH’s definition and history as well as how pH is determined and measured.
pH means “potential of hydrogen”, and is a chemical scale of acidity or basicity.The pH level goes from 0 to 14, with 7 being neutral, under 7 acidic, over 7 basic.The pH scale is logarithmic, so every value of 1 on the pH scale is a 10 times difference in acidity or basicity.For instance, solution having pH 4 is 10 times acidic than solution having pH 5 [1].
The Danish chemist Soren Peder Lauritz Sorenson introduced the concept of pH in 1909.He invented the pH scale to be able to measure acidity or basicity in one number, and then compare and describe the acidity/basicity of various solutions [2].
Depending on the pH, pH test strips, pH paper, pH meters and other types of tests are available.The pH test strips and pH paper are for routine, off-site measurements, pH meters are better-accurate and are often employed in the lab and industry [3].
When we want to know the pH of a solution, we need to take a measurement of the level of hydrogen ions (H+) in the solution.The pH of the solution is the negative logarithm (base 10) of the H+ level.This is often summed up mathematically: pH = -log[H+] [4].
Conclusion: pH is a key term in water chemistry that’s used to indicate the acidity or basicity of a solution.Its pH scale runs from 0 to 14, and 7 is neutral, less than 7 acidic, and above 7 basic.The pH scale is an invention of Soren Peder Lauritz Sorenson from 1909 and there are various ways to determine the pH, such as pH test strips, pH paper and pH meters.Knowing about pH, what it is and how it is measured and computed is critical in many fields from monitoring rivers and ponds to industrial production.
[1] “pH.” National Institutes of Health, U.S. National Library of Medicine, MedlinePlus,
[2] “Soren Peder Lauritz Sorensen.” Encyclopædia Britannica, Encyclopædia Britannica, Inc.
[3] “pH Measurement.” Hach,
[4] “pH and Water.” Water Research Center,
The pH scale
The pH scale is an idea in water chemistry that defines acidic, neutral or basic.In this article, we will discuss the pH scale and how it’s used to rank substances according to acidity or basicity.
This is a log scale called pH (from 0 to 14).The less than 7th number on the pH scale is acidic, and the more than 7th number is basic.The pH scale is logarithmic which means that every 0 on the pH scale corresponds to a 10 times greater acidity or basicity.A solution with pH 4 for instance is 10 times more acidic than a solution with pH 5 [1].
The pH scale refers to the class of fluids — water, soil, etc.Water that is 7 or higher, for instance, is neutral, and water with a pH lower than 7 is acidic and water with a pH above 7 is basic.Soil pH of 7 is neutral, soil pH less than 7 acidic, and soil pH higher than 7 basic [2].
We must not forget that the pH scale is not just applied to liquids and solids, but also to gases.pH : The acidity or basicity of a gas is normally expressed as moles of H+ or OH- ions per liter of air.Air that is neutral, for instance, is acidic, while air with a pH less than 7 is basic.
This is another fact that the pH scale doesn’t only apply to natural materials, it is also applied to a wide range of industrial processes.For instance, industrial effluent pH — like the effluent from a factory — should be checked so it’s within acceptable levels for discharge into a natural waterway.
Bottom line: The pH scale is a basic mathematical unit in water chemistry that allows you to categorise substances by their acidity or basicity.It has a pH of 0-14 with 7 being neutral, less than 7 being acidic, and more than 7 being basic.The pH scale is logarithmic and each point higher or lower than 1 in the pH scale is 10 times more acidic or basic.We can categorise any matter (water, soil, other liquids, gases and most industrial processes) using the pH scale.Understanding pH scale and what you need to know about it can be applied to anything from monitoring the surface of water in the natural environment to the industrial process.
[1] “pH Scale.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., www.britannica.com/
[2] “Soil pH.” USDA, United States Department of Agriculture,
The importance of pH in water
The pH influences water processes and systems as far back as the mineral solubility of water, aquatic life and water-treatment systems.We will be studying pH in water and how pH can impact different elements of water chemistry in this paper.
pH determines the water’s soluble minerals, which can affect whether fish have the proper nutrients and minerals they need.For instance, low pH metals like iron and manganese are more soluble and, at high levels, toxic to aquatic organisms.Minerals like calcium and magnesium dissolve less easily in high pH, and build up to clog water pipes and other appliances [1].
For aquatic life, pH is also essential.Most living organisms are adapted to a specific pH range, and a change in pH can make or break survival and reproduction.Acidic water, for instance, is toxic to fish and other aquatic life; and basic water can stop some species from growing and reproducing [2].
pH also determines how effective water treatment systems like chlorine treatment are.Chlorine is best disinfecting between pH of 7.2 and 7.8; its performance drops outside this point [3].
As a pH control is critical to the health and safety of aquatic ecosystems, as well as the functioning of water treatment systems.It is achieved with pH measurement and control — pH test kits, pH meters, pH controllers.
pH, in short, is fundamental to many processes and systems within water – from the mineral solubility, to the biology of aquatic life, to the performance of water treatment.It’s important to know what pH is in water to help keep aquatic life healthy and safe, and water treatment systems running effectively.Using monitoring and controlling pH levels can also be used to control the pH of water so it remains in a safe and appropriate range for a variety of purposes.
[1] “Water Chemistry – pH and Water.” American Water Works Association,
[2] “pH in Aquatic Systems.” Water Quality Association,
[3] “Water Disinfection: Chlorine.” US Environmental Protection Agency,
Factors that affect water pH
pH of water depends on a host of different conditions – chemical reactions, biology, the weather.We will learn here how the pH of water is affected by other factors that affect it and also the effects they have on the pH of water.
The main reason water pH can be affected are chemical reactions.For instance, if you add acids or bases to water, the pH level might vary.Acid rain, the result of the emissions of sulfur dioxide and nitrogen oxides into the atmosphere, is one way that chemicals change water pH.These gases will decompose in rainwater to create sulfuric acid and nitric acid which neutralizes water [1].
So can biological activities like the breathing of aquatic life, affecting the pH of water.Ocean animals breathe in carbon dioxide, which can become carbonic acid and pH-change the water.And also the organic matter degradation by microorganisms can affect the pH of water, since organic matter degradation can give off acids which depauperate water [2].
Even ambient conditions like temperature and sunlight affect pH of water.Water that’s warmer, for instance, can contain less dissolved gas and hence has higher pH.Sunlight can also lead to photosynthesis, which accrose water’s pH by excreting oxygen [3].
Not only that, but water pH can be influenced by human inputs, such as industrial discharge and agriculture, including the use of fertiliser, that introduce acids and bases into water.
So, in short, water pH is a product of a host of different mechanisms: reactions, biochemistry, environmental influences.All of these can alter pH, and can have massive effects on aquatic environments and human activity.You need to know how water pH is impacted by multiple factors so that you can monitor and regulate water quality and make sure that pH levels remain within a safe and acceptable range for applications.
[1] “Acid Rain.” United States Environmental Protection Agency, www.epa.gov/
[2] “Biological Factors That Affect Water Quality.” Water Research Center,
[3] “Temperature and pH.” Water Quality and Treatment, sixth edition, American Water Works Association, 2011.
Measuring and monitoring water pH
Water pH describes how acid or basic water is, which if it is 7 then it’s neutral.pH in water should be monitored and controlled for the quality of water since changes in pH can have major consequences on aquatic ecosystems and human behaviour.In this article, we will examine some methods and devices to measure and keep track of the water pH like pH meters and pH paper.
pH meters are the most used water pH instrument.They measure this potential between two electrodes and it is directly proportional to the water pH.It is the most accurate and precise pH meters, but they need to be calibrated and maintained for reliable reading [1].
The other very popular pH measuring technique for water is pH paper.pH paper is a paper that recolors as the water pH.The hue is compared to a typical color graph to get the pH of the water.pH paper is rather easy to operate, but is far from being accurate and precise as pH meters [2].
There are other ways and instruments, beyond pH meters and pH paper, to check and regulate water pH such as colorimetry, ISE (ion-selective electrodes) [3].Colorimetric techniques (like pH indicators) like pH paper, for example, work on the basis of a colour shift to show the pH of the water.But they are more reliable and precise than pH paper.ISEs are electrodes with the ability to sense particular ions in water (eg, hydrogen ions) and they’re very selective and sensitive.
It is also worth mentioning that pH of water should also be recorded periodically in order to detect and react to pH fluctuations.Whether that be by regularly taking water samples and measuring pH levels, or by putting in continuous monitoring systems like automatic water samplers.
As you can see pH testing and water monitoring is very relevant for water quality.It’s possible to use a pH meter, pH paper, colorimetric method, or ion-selective electrode as some of the ways and devices that you can quantify and track the water’s pH.The most reliable and precise is the pH meters, but they have to be calibrated and tended to.You should be familiar with the many ways and tools to test and monitor water pH for monitoring and treating water quality and to ensure that pH remains within a safe, appropriate range for various uses.
[1] “pH Meters.” Hach,
[2] “pH Testing.” LaMotte,
[3] “Water pH Measurement.” Thermo Fisher Scientific,
pH in natural water systems
Water pH is a measure of the acidity or basicity of water and is an important aspect of water quality. In natural water systems, the pH can vary widely depending on the specific water body and the surrounding environment. In this paper, we will investigate the pH of different natural water systems, such as rivers, lakes, and oceans, and how it is affected by various factors. We will also explore how human activities, such as industrial waste discharge and agricultural runoff, can impact these pH levels. Additionally, we will examine the pH levels in reverse osmosis water, which is often treated to achieve a neutral pH but can vary depending on the source water quality. Understanding these dynamics is crucial for maintaining ecological balance and ensuring safe water for consumption and recreational activities.
Rivers and streams generally have a neutral to slightly alkaline pH, with an average pH of around 7.5. However, the pH of rivers and streams can vary widely depending on the surrounding environment and the specific water body. For example, rivers that flow through areas with a high concentration of limestone will tend to have a higher pH due to the presence of dissolved calcium carbonate [1]. On the other hand, rivers that flow through areas with a high concentration of acid-producing rock, such as granite, will tend to have a lower pH.
Lakes, like rivers, generally have a neutral to slightly alkaline pH, with an average pH of around 7.5. However, the pH of lakes can vary depending on the specific lake and the surrounding environment. For example, lakes that are located in areas with a high concentration of acid-producing rock will tend to have a lower pH, while lakes that are located in areas with a high concentration of limestone will tend to have a higher pH. Additionally, the pH of lakes can also be affected by human activities such as agricultural runoff, which can introduce acids and bases into the water [2].
Oceans and seawater generally have a pH of around 8.1, which is slightly alkaline. The pH of seawater is influenced by a variety of factors, including the dissolution of carbon dioxide, the weathering of rocks, and the uptake of carbon dioxide by marine organisms through photosynthesis. However, the pH of oceans is currently decreasing due to the increase in atmospheric carbon dioxide levels caused by human activities, a process known as ocean acidification [3]. This decrease in pH can have significant impacts on marine ecosystems, as it can affect the growth and survival of marine organisms, particularly those with calcified shells or skeletons, such as corals and shellfish [4].
In conclusion, the pH of natural water systems, such as rivers, lakes, and oceans, varies depending on the specific water body and the surrounding environment. The pH of rivers and lakes can be affected by the presence of dissolved minerals and human activities, while the pH of oceans is affected by a variety of natural and anthropogenic factors. Understanding the pH of different natural water systems is essential for monitoring and managing water quality and for understanding the impacts of human activities on these systems. It is also important to note that the pH of natural water systems is constantly changing, and it is important to continue monitoring and studying these changes to identify potential impacts and to develop strategies to mitigate any negative effects.
[1] “pH of water” United States Geological Survey.
[2] “Impact of Agricultural Runoff on Water Quality” United States Environmental Protection Agency.
[3] “Ocean Acidification” National Ocean Service.
[4] “Ocean Acidification and Marine Biodiversity” United Nations Environment Programme.
pH in domestic and industrial water systems
Water pH is a measure of the acidity or basicity of water and is an important aspect of water quality. In natural water systems, the pH can vary widely depending on the specific water body and the surrounding environment. In this paper, we will investigate the pH of different natural water systems, such as rivers, lakes, and oceans, and how it is affected by various factors.
Rivers and streams generally have a neutral to slightly alkaline pH, with an average pH of around 7.5. However, the pH of rivers and streams can vary widely depending on the surrounding environment and the specific water body. For example, rivers that flow through areas with a high concentration of limestone will tend to have a higher pH due to the presence of dissolved calcium carbonate [1]. On the other hand, rivers that flow through areas with a high concentration of acid-producing rock, such as granite, will tend to have a lower pH. Additionally, human activities such as industrial discharge and agricultural practices, can also affect the pH of rivers and streams by introducing acids and bases into the water [2].
Lakes, like rivers, generally have a neutral to slightly alkaline pH, with an average pH of around 7.5. However, the pH of lakes can vary depending on the specific lake and the surrounding environment. For example, lakes that are located in areas with a high concentration of acid-producing rock will tend to have a lower pH, while lakes that are located in areas with a high concentration of limestone will tend to have a higher pH. Additionally, human activities such as agricultural runoff and urbanization can also affect the pH of lakes by introducing pollutants into the water [3].
Oceans and seawater generally have a pH of around 8.1, which is slightly alkaline. The pH of seawater is influenced by a variety of factors, including the dissolution of carbon dioxide, the weathering of rocks, and the uptake of carbon dioxide by marine organisms through photosynthesis [4]. However, the pH of oceans is currently decreasing due to the increase in atmospheric carbon dioxide levels caused by human activities, a process known as ocean acidification [5]. This decrease in pH can have significant impacts on marine ecosystems, as it can affect the growth and survival of marine organisms, particularly those with calcified shells or skeletons, such as corals and shellfish [6].
In conclusion, the pH of natural water systems, such as rivers, lakes, and oceans, varies depending on the specific water body and the surrounding environment. The pH of rivers and lakes can be affected by the presence of dissolved minerals and human activities, while the pH of oceans is affected by a variety of natural and anthropogenic factors. Understanding the pH of different natural water systems is essential for monitoring and managing water quality and for understanding the impacts of human activities on these systems. It is also important to note that the pH of natural water systems is constantly changing, and it is important to continue monitoring and studying these changes to identify potential impacts and to develop strategies to mitigate any negative effects.
In order to effectively monitor and manage the pH of natural water systems, it is important to have proper regulations and guidelines in place to limit the amount of pollutants and acids entering the water. Additionally, monitoring and measuring pH levels regularly and using appropriate methods and instruments is crucial in identifying changes in pH levels and determining the impact of human activities on the natural water systems. Furthermore, research and development of new technologies and techniques to mitigate the negative impacts of human activities on pH levels is also important.
[1] “Limestone and Acid Rain,” Chemical Education Research Group, University of Limerick,
[2] “Acid Rain: Causes, Effects, and Solutions,” Environmental Defense Fund,
[3] “Agricultural Runoff,” United States Environmental Protection Agency,
[4] “The Carbon Cycle and Seawater pH,” National Ocean Service,
[5] “Ocean Acidification,” National Ocean Service,
[6] “Ocean Acidification and Marine Organisms,” National Ocean Service,
The effects of pH on water quality
Water pH is an important aspect of water quality, as it can have a significant impact on the overall quality of water, including its taste, appearance, and suitability for various uses. In this paper, we will examine the effects of pH on water quality and the implications of these effects for water management and treatment.
One of the most significant effects of pH on water quality is its impact on the taste and appearance of water. Water with a pH that is too high or too low can have a bitter or metallic taste, which can make it unappealing to drink. Additionally, water with a pH that is too high or too low can also cause discoloration, staining, and cloudiness, which can make it unappealing to look at. These effects can be particularly pronounced in the case of acidic water, which can cause corrosion of pipes and fixtures, leading to the release of metals and other contaminants into the water [1].
Another important effect of pH on water quality is its impact on the suitability of water for various uses. Water with a pH that is too high or too low can be harmful to aquatic life, as it can disrupt the balance of essential elements in the water, making it difficult for organisms to survive [2]. Additionally, water with a pH that is too high or too low can be harmful to humans, as it can cause skin and eye irritation and can aggravate respiratory conditions [3]. Water pH also affects the efficacy of chemical treatment processes, such as disinfection and coagulation, which are commonly used in water treatment plants [4].
To mitigate the effects of pH on water quality, it is important to monitor and measure pH levels in water sources, and to take appropriate action to adjust pH levels as needed. This can include adding chemicals such as lime or soda ash to raise pH levels, or adding acid to lower pH levels. Additionally, water treatment processes, such as filtration and ion exchange, can also be used to remove contaminants and adjust pH levels.
In conclusion, the pH of water can have a significant impact on the overall quality of water, including its taste, appearance, and suitability for various uses. Understanding the effects of pH on water quality is essential for monitoring and managing water quality and for ensuring that pH levels are within a safe and suitable range for various applications. It is important to regularly monitor and measure pH levels in water sources, and to take appropriate action to adjust pH levels as needed. Additionally, water treatment processes can be used to remove contaminants and adjust pH levels, to ensure that the water is safe for human consumption and for aquatic life. It is also important to consider the potential long-term impacts of human activities on water pH, such as the effects of industrial discharge and agricultural practices, to minimize negative effects on water quality.
[1] “Corrosion and water/wastewater treatment.” (n.d.).
[2] “Water pH and fish health.” (n.d.).
[3] “Effects of pH on the human body.” (n.d.).
[4] “Water pH and its effects on the treatment process.” (n.d.).
pH and water-related health issues
Water pH is an important aspect of water quality, as it can have a significant impact on the health of humans and animals. In this paper, we will investigate the potential health effects of pH on humans and animals, including the risks of acidosis and alkalosis.
Acidosis is a condition that occurs when the pH of the body’s fluids, including blood, becomes too acidic. This can occur due to a variety of factors, including the consumption of acidic water, metabolic disorders, and certain medical conditions. Acidosis can cause a range of symptoms, including fatigue, confusion, and shortness of breath and can lead to serious complications if left untreated [1].
Alkalosis, on the other hand, is a condition that occurs when the pH of the body’s fluids becomes too alkaline. This can occur due to a variety of factors, including the consumption of alkaline water, certain medical conditions, and the use of certain medications. Alkalosis can cause a range of symptoms, including muscle twitching, tingling, and confusion, and can also lead to serious complications if left untreated [2].
The consumption of water with a pH that is too high or too low can also have other potential health effects. For example, acidic water can cause corrosion of pipes and fixtures, which can lead to the release of harmful contaminants into the water, such as lead and copper [3]. Additionally, water with a pH that is too high or too low can also cause skin and eye irritation and can aggravate respiratory conditions [4].
To minimize the risks of acidosis and alkalosis, it is important to ensure that the pH of drinking water is within a safe and suitable range. The World Health Organization recommends a pH range of 6.5-8.5 for drinking water [5]. Additionally, it is also important to be aware of the potential health effects of consuming water with a pH that is outside of this range, and to seek medical attention if experiencing symptoms of acidosis or alkalosis.
Furthermore, it is also important to consider the long-term effects of consuming water with a pH that is outside of the safe range. For example, a chronic exposure to acidic water can lead to a loss of bone density and an increased risk of osteoporosis. Also, in animals, chronic exposure to acidic water can lead to chronic acidosis, which can cause a variety of health problems, including growth retardation, decreased immunity and increased susceptibility to disease, and reduced fertility.
In conclusion, pH is an important aspect of water quality, as it can have a significant impact on the health of humans and animals. The risks of acidosis and alkalosis can be minimized by ensuring that the pH of drinking water is within a safe and suitable range, and by being aware of the potential health effects of consuming water with a pH that is outside of this range. It is also important to consider the long-term effects of consuming water with a pH that is outside of the safe range and to seek medical attention if experiencing symptoms of acidosis or alkalosis.
[1] “Acid-base imbalance.” MedlinePlus, U.S. National Library of Medicine,
[2] “Alkalosis.” Mayo Clinic, Mayo Foundation for Medical Education and Research,
[3] “Corrosion in Drinking Water Distribution Systems.” Environmental Protection Agency, United States Environmental Protection Agency,
[4] “Water pH and Your Health.” pH Pure Water, www.phpurewater.com/
[5] “WHO | Guidelines for drinking-water quality.” World Health Organization, World Health Organization,
Managing and adjusting water pH
Water pH is an important aspect of water quality and managing and adjusting the pH of water is essential for ensuring that it is safe for human consumption and aquatic life. In this paper, we will explore various methods for managing and adjusting the pH of water, including the use of pH-adjusting chemicals and natural methods.
One of the most common methods for managing and adjusting water pH is the use of pH-adjusting chemicals. These chemicals are added to water to raise or lower the pH as needed. For example, lime (calcium hydroxide) and soda ash (sodium carbonate) are commonly used to raise the pH of water, while sulfuric acid and hydrochloric acid are commonly used to lower the pH [1]. These chemicals are added in small doses and are carefully monitored to ensure that the pH remains within a safe and suitable range.
Another method for managing and adjusting water pH is the use of natural methods. For example, adding crushed limestone to water can help to raise the pH, while adding peat moss or pine needles can help to lower the pH [2]. Additionally, certain types of vegetation, such as cattails and bulrushes, can also help to naturally adjust the pH of water [3]. These natural methods can be used in conjunction with chemical methods or as an alternative to chemical methods.
Another method for managing pH is to use ion exchange process, which can be done by using resin beads to adsorb H+ ions, or by using a chemical solution to regenerate the resin beads.
It is important to note that while managing and adjusting the pH of water can help to ensure that it is safe for human consumption and aquatic life, it is also important to consider the potential long-term impacts of these methods. For example, the use of pH-adjusting chemicals can lead to the release of harmful contaminants into the water, and can also have negative impacts on the environment [4]. Additionally, natural methods may not always be suitable or effective in all situations.
In conclusion, managing and adjusting water pH is essential for ensuring that water is safe for human consumption and aquatic life. There are various methods available for managing and adjusting water pH, including the use of pH-adjusting chemicals and natural methods. It is important to carefully consider the potential long-term impacts of these methods and to choose the most appropriate method based on the specific situation. Regular monitoring and testing of water pH is also necessary to ensure that the pH remains within a safe and suitable range.
[1] “pH adjustment.” Water Treatment Solutions, Hydram Engineering,
[2] “Natural pH adjustment for ponds and lakes.” Aquatic Eco-Systems, Inc.,
[3] “Vegetation for water pH adjustment.” The Pond Clinic, www.pondclinic.com/
[4] “The impact of pH adjustment on water quality and the environment.” Water Research, vol. 45, no. 14, 2011, pp. 4193-4205.,
Share this research on social media
See all Research on PH
See All
Read More
PrevPreviousThe Link Between Lead in Drinking Water and Agricultural Practices, The Role of Lead Testing
NextUnderstanding the Different Types of Lead Contaminants and Their Testing ChallengesNext
