- Insufficient chlorine
- Excess addition of acid to swimming pool water
- Use of products containing cyanuric acid
- Weather conditions
All dosages are based on an average pool with a capacity of 50 000 litres. Adjust according to your pool size, regional variations and weather conditions.
Note: To raise pH in fibreglass pools, only HTH® Alkalinity Up should be used.
In the case of a vinyl or coloured lining, add HTH® Alkalinity Up directly into the weir to prevent possible bleaching.
- To prevent possible staining from metals that may be present in your water, add 1 bottle of HTH® Metal Remover – follow label directions.
- With the pump running on the filter setting, add cup (250g) of HTH® Alkalinity Up around the slides of the pool.NB: in the case of a vinyl or coloured pool lining, add HTH® Alkalinity Up directly into the weir.
- Filter for 3 – 4 hours. Test pH and readjust if necessary.
- HTH® Metal Remover
- HTH® Alkalinity Up