|Problem ||Possible Cause ||Check / Remedy
||Sanitiser level low. Sunlight dissipating sanitiser. High pH reducing sanitiser effectiveness. Not using preventative Algaecide.
||Ensure sanitiser / cyanuric acid levels are adequate throughout the pool. Reduce pH to recommended range of 7.2 – 7.6, Use maintenance algaecide dose.
|Calcium hardness too high / scale formation.
||Build-up of calcium salts.
||If mains water has a lower calcium level, dilute the pool. Add a monthly dose of Stain & Scale Inhibitor.
|Calcium hardness too low / pool grouting soft or eroding.
||Soft mains water supply.
||Increase calcium hardness level to a minimum of 200ppm.
||Build-up of swimmer pollution. Inadequate sanitiser levels. Cyanuric acid too high. Ineffective filtration. Water not ‘balanced’ correctly.
||Check sanitiser levels and if necessary shock dose the pool. Dilute to reduce cyanuric acid levels. Filter media needs cleaning / changing. Check water balance and adjust if required.
|Chlorine level low / difficult to maintain.
||Lack of sanitiser / cynauric acid. High bather load / prolonged hot weather.
||Increase sanitiser dose and if necessary adjust cyanuric acid levels. More frequent shock dosing may be required.
|Chlorine reading is zero using test kit despite chemical additions.
||Chlorine level may be too high causing test reagents to bleach. Chlorine demand (very high build-up of pollutants).
||Allow sanitiser level to drop naturally / lower using Chlorine Reducer or dilute by partially draining and refilling. Continue to shock dose pool water if over-chlorination is not the cause.
|Chlorine level is high
||Allow sanitiser level to drop naturally, lower using Chlorine Reducer or dilute by partially draining & refilling.
||Copper in pool water precipitating
||Test copper level. Check water balance and adjust if necessary. Add an initial dose of Stain & Scale Inhibitor. For sand filters, also use Aquasparkle Tabs or Flockfix Cartridges to aid with copper removal.
|pH level high
||High pH of mains water. Alkaline shock treatment being used.