Neutral pH – Balanced
If the pH is balanced, it means that the water is neither corrosive nor scale forming. The neutral point for pool water, generally between 7.2 and 7.6, is slightly higher than the neutral point for water in general (7.0). This is because the surface that your pool water comes into contact with is generally basic by nature (pool plaster, grout, tile, etc.), so the pool water must be a bit more basic to accommodate it.

Low pH – Acidic
A pH level lower than 7.0 indicates that the water is acidic so it tends to corrode. To increase the pH level, a pH increaser (sodium carbonate (also known as soda ash) is broadcast or sprinkled in your pool water. Sodium Carbonate, a granular product, is typically packaged and sold as “pH Up”, pH Increaser”, or pH Plus. Always read the instructions on the label before adding any type of pH decreaser, as manufacturers will recommend varying amounts to add per 10,000 gallons of water as well as the specific procedures.

Factors that can lead to low pH:

• Tap water in certain areas has a low pH.
• Overestimating the amount of pH Decreaser used.
• Using chlorine tablets, or bromine, will lower pH over time.
• High bather loads.
• Swimmer wastes, such as perspiration, urine, saliva and other body oils.
• dirt, debris or leaves that blown into the pool.
• The acidic level of rain can also lower pH.

High pH – Basic
A pH level higher than 7.0 indicates that the water is basic or alkaline so it tends to scale. To decrease the pH level, a pH decreaser (sodium bisulfate (also called "dry acid") or muriatic acid) is broadcast or sprinkled in your pool water. Sodium bisulfate is a granular product, typically packaged and sold as “pH Decreaser”, “pH Down”, or “pH Minus”. Muriatic acid is a liquid. Always read the instructions on the label before adding any type of pH decreaser, as manufacturers will recommend varying amounts to add per 10,000 gallons of water as well as the specific procedures.

Factors that can lead to high pH:

• Tap water in certain areas has a high pH.
• Overestimating the amount of pH Increaser used.
• Shocking the pool with Calcium Hypochlorite or Lithium Hypochlorite will raise the pH value over time.
• A high alkalinity reading.

pH Overview		Total Alkalinity