Spa water accumulates a build-up of waste material with use over time. This waste material eventually turns water cloudy, dull and irritating to the bathers. These wastes cannot be eliminated from the water by normal filtration. Oxidization only will rid the spa of these non-filterable wastes and restore the sparkling appearance to the water. Oxidization should be carried out on a regular basis and forms part of the ‘Unique Routine Management’ of a spa.
Total dissolved solids (TSD) consist of dissolved chemicals and minerals in the spa water. TDS accumulates through normal use of maintenance chemicals, evaporation and their presence in added water. Excessive TDS reduces chemical efficiency and loss of water clarity. This is the point at which the spa will not respond to normal treatment. Your spa will need to be refreshed with clean low TDS water (refreshing is removing some existing water and adding clean water at the same time). This process should be carried out on a regular basis and forms part of the ‘unique routine management’ of a spa.
How often you refresh your spa depends on how often you use it. Here is a formula that has been supplied for non-salt spas and assumes the manual addition of sanitizer powder every day (a salt spa should not have to be drained as often as given in this formula)
Spa Litres ÷ Daily Bathers ÷ 12 = Days between Draining
Example: 1200 litres ÷ 2 daily bathers’ ÷ 12 = 50 days
Important Tip: When all things you usually do don’t work, it is time to start again with fresh water. Note – in grounds spas should only be refreshed – never emptied as they can lift out of the ground