Regular testing of a hot tub is an essential part of your routine to look after and maintain your water chemistry. Without testing the water you could be putting yourself and the spa at risk. The most important levels to test for are the Sanitiser and pH levels. The correct level for Chlorine or Bromine is between 3.0mg/l and 5.0mg/l whilst the correct level for the pH should be between 7.2 and 7.6. These should be tested every day as the balance can shift easily within 24 hours. Not only can unbalanced water be unpleasant to bathe in it can also be corrosive to the hot tub itself.