Balancing Water Chemistry: How to Balance Your Pool pH Level


One of the most important steps of swimming pool maintenance is learning to maintain your pool water’s chemical balance. Getting it right can help ensure that your pool water stays fresh and clean, and you can avoid common pool maintenance pitfalls.

Not a chemistry buff? No worries. You don’t have to be a science whiz to learn the ins and outs of testing your water and adjusting the pH of your swimming pool. All you need is some basic knowledge and a good test kit.

What is pH?

First things first: pH is a measure of the acidity of your pool water – and it can affect everything from algae growth and corrosion to comfort and cleanliness. Your water’s pH can also affect the effectiveness of other chemicals in your swimming pool.

Ideally, you want your pH to be between 7.2 and 7.8. Levels below 7.2 indicate acidic water. To reverse this, use a pH increaser to balance the water. If your water’s pH is above 7.8, that means it’s high in alkalinity. In that case, you can you can add a pH decreaser.

Your pool chemistry can be affected by several factors, including:

  • Pool usage
  • Heavy rainfall
  • Temperature
  • Whether you have “hard” or “soft” water
  • High bather load

Salt Water and pH

Salt chlorine pools have a different chemical makeup than traditional chlorine pools, and they are more prone to having a higher pH. If you have a salt water pool, keep an eye on the numbers and have a pH decreaser on hand.

Why is pH Balance Important?

Why does pH balance matter? Here are just a few reasons to maintain a balanced swimming pool:

  • It helps chlorine work effectively. Chlorine is essential for keeping your pool clean and free of potentially harmful germs and bacteria. The catch? For chlorine to work effectively, your swimming pool water has to be balanced properly. If your pH is too high or too low, chlorine won’t be working at full strength.
  • It makes your pool water easy on the eyes (literally and figuratively). Keeping your pool water balanced will help prevent unsightly mineral buildup and algae growth – and it also ensures that your pool is gentle on your eyes (pH at improper levels can cause irritation).
  • It prevents corrosion and irritation. If your pool’s pH is too low, the water will corrode your pool’s metal components (thinks ladders, hand rails, and pool pump elements). Maintaining a proper pH will also ensure that your pool water is gentle to the skin.

Pool Chemistry Terms to Know

Total Alkalinity. Alkalinity is what neutralizes the acids in your swimming pool water, and alkalinity that’s too high or too low can lead to a wide range of issues, from minor skin irritation to algae growth and cloudy water. Alkalinity also directly affects your pool water’s pH: If your pool’s total alkalinity is too high, your pH will be too high. Alternatively, if your total alkalinity is too low, your pH will also be too low. Total alkalinity is usually measured in parts per million (PPM). Ideally, you want a total alkalinity of around of 100 PPM.

To reduce your swimming pool water’s total alkalinity, you can add muriatic acid or a dry pH increaser (preferred). Add an alkalinity increaser to raise total alkalinity. Looking for pool chemicals? Find a pool chemical retailer near you.

Know the Lingo: Parts Per Million

Parts per million – often abbreviated as PPM – is a unit of measurement that tells you how much of a particular substance – such as a chemical or mineral -- is present in water.

Stabilizer. Available in liquid or powdered form, pool stabilizer helps preserve the chlorine levels in your pool protect them from the breakdown effects of sunlight. When your stabilizer level is low, you'll use a lot more chlorine. When it's high, you may need to dilute your pool water to bring it back into the ideal 40 to 100 PPM range.

A Stabilizer by Any Other Name...

Pool water stabilizer is also known as conditioner or the more scientific-sounding cyanuric acid. No matter what you call it, though, it’s important not to add too much (overdoing it can make your chlorine less effective).

Total Dissolved Solids (TDS). This term is a catch-all that includes everything from naturally occurring minerals to debris and dust to organ buildup that occurs from everyday use. compounds. As your swimming pool water evaporates, leaving behind concentrated, hard-to-remove TDS deposits – which, in turn, can make pool chemicals less effective and create stains. If you have 3000 PPM or more of TDS, you may need to drain some water and add fresh water.