Poolside by CGT Vinyl Pool Technical Manual

What Is the Ideal Pool Water Chemistry for Vinyl Pool Liners?

Maintaining balanced pool water chemistry levels is essential for protecting vinyl pool liners and keeping swimming pool water safe and clear.

Pool and Liner Care

Maintaining correct pool water chemistry is essential for keeping the pool sanitary and enjoyable.

Pool chemicals are highly concentrated and should always be handled according to manufacturer instructions.

CGT recommends reviewing the Poolside by CGT Vinyl Pool Maintenance Manual for detailed recommendations on maintaining water chemistry.

pH Levels
7.2 – 7.6

Free Chlorine
1.0 – 3.0 ppm

Cyanuric Acid
Stabilizer Level
25 – 50 ppm

FAQ

Why is water chemistry important for vinyl pool liners?

Balanced water chemistry helps prevent liner damage, algae growth, and cloudy pool water.

Alkalinity
Total alkalinity refers to the buffering capacity of pool water. The recommended rang is 80-120 ppm.

Maintaining proper alkalinity helps stabilize pH levels and prevents rapid fluctuations in water chemistry.

Sodium bicarbonate is commonly used to increase alkalinity.

As a general rule:
1.5 pounds of sodium bicarbonate added to 10,000 gallons of water will raise alkalinity by approximately 10 ppm.

How do you raise pool alkalinity?

Pool alkalinity is commonly raised using sodium bicarbonate, also known as baking soda.

What happens if pool alkalinity is too low?

Low alkalinity can cause unstable pH levels and increase the risk of corrosion.

Calcium Hardness
Calcium hardness measures the amount of dissolved calcium in pool water. The recommended range is 200-400 ppm.

If calcium hardness levels are too low, the water may become corrosive.
If calcium hardness levels are too high, scaling may occur.
Calcium chloride is commonly used to raise calcium hardness.

Reducing calcium hardness may require partially draining the pool and refilling with fresh water.

What happens if calcium hardness is too high in a pool?

High calcium hardness can lead to scaling on pool surfaces and equipment.

Can low calcium hardness damage pools?

Low calcium hardness can make water corrosive and may damage fixtures or equipment.

pH
pH measures the acidity or alkalinity of pool water.

The recommended pH range for swimming pools is 7.2 to 7.6.
Pools naturally tend to drift toward higher pH levels over time.

Common chemicals used to adjust pH include:

Muriatic acid
Sodium bisulfate (dry acid)
Sodium carbonate (soda ash)

Direct contact between strong acids and vinyl liners should be avoided.

What is the ideal pH level for a swimming pool?

The ideal pool pH level is between 7.2 and 7.6.

How often should pool pH be tested?

Pool pH should typically be tested several times per week during the swimming season.

These guidelines reflect best practices outlined in the Poolside by CGT Vinyl Pool Technical Manual.