With spa and hot tub use increasing, we’ve put together a handy spa chemistry guide with all the information you need to manage the water chemistry of your spa. The spa guide provides you with definitions of the key parameters that are most important for spa management, a guide to the recommended levels and the effects of poor water monitoring.
Bromine in Spas-Recommended bromine levels in the UK for pools and spas are 4.0 – 6.0 mg/L with shock dose of 10 mg/L.
Calcium Hardness in Spas – Calcium hardness should be measured once a week, and a level between 80 – 200 mg/L maintained.
Chlorine (Free and Total) in Spas – If chlorine is being used in a well-designed spa you should be looking for a free chlorine residual of 3.0 – 5.0 mg/L. The combined chlorine should be as low as possible and certainly less than half the free and never more than 1 mg/L.
Cyanuric Acid in Spas – Levels should be below 200 mg/L, with many authorities suggesting levels between 25 and 50 mg/L are ideal.
pH in Spas – Ideally you are looking for a pH of 7.2 – 7.4, an overall range of 7.0 – 7.6 is acceptable in most spas.
Phosphate in Spas – The level of total phosphates in the spa water should be 0.01 mg/L or below.
Total Alkalinity in Spas – Levels should be in the range 80 – 200 mg/L CaCO3.
Turbidity in Spas – The level of turbidity should be 0.5 NTU (Nephelometric Turbidity Units) or less.
Palintest always recommends that you seek advice on your local authority legislation.
14th June 2022
Ammonia is naturally found in water, as it is produced through the decay of organic matter as well as by humans through the production of fertilisers, plastics, pharmaceuticals, and petrochemicals.