Stains & Scale

Don't let stain and scale build up and become hard to remove. Let us show you how to stay on top of the problem.

Stains & Scale

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Iron, copper and manganese can cause green, brown and purple stains on pool surfaces. Leaves, sticks and other organic debris can cause brown stains on pool surfaces.

Recommended solutions

- Take action as soon as the stains are noticed.

- Ensure water is properly balanced. Lower pH to 7.2-7.4.

- Brush the stained areas daily for at least 5-7 minutes using an 18" curved wall brush.

- Use HTH™ Metal, Stain and Scale Control according to label directions.

- Organic stains will slowly disappear with the regular use of chlorine sanitizer and shock products.

- Brush the stained areas to help remove the stain.


Higher levels of calcium combined with high pH and/or high Total Alkalinity (TA) can cause scale buildup on pool surfaces. Scale is noted by the off-white, gray or tan color, rough texture and release of chalky dust when brushed.

Recommended solutions

- Check and adjust water balance. Adjust pH to the lower end of the range (7.2-7.4).

- Use HTH™ Metal, Stain and Scale Control according to label directions.

- Brush the scale areas at least daily. More frequent brushing will help speed up the removal of the scale.

- If softer water is available, the Calcium Hardness (CH) level can be reduced by draining some of the water in the pool and replacing it with softer water.

Preventative maintenance

- Maintain water balance parameters at all times.

- If the fill water already has high hardness, keep the pH and Total Alkalinity (TA) in the lower half of their respective ranges.

- Add HTH™ Metal, Stain and Scale Control weekly.

As always, we’re here to help. If you have questions, contact our help line at 1-866-HTH-POOL or talk to our experts with our live chat!


Please read the following important reminders before adding pool chemicals to water:

• NEVER mix products together or dissolve before use.

• ONLY enter pool when FAC levels are below 4 ppm to prevent risk of bodily harm.