Water Testing
If you are using chlorine or bromine to sanitise your hot tub then it is important to constantly monitor the pH of the water and to measure your hot tub chemicals levels.
If you are using an Active Oxygen based sanitising system then testing is far less important because the efficacy of product isn't affected by the pH of the water, in the same way that chlorine and bromine are.
Test water close to the middle of the tub at about elbow deep.
Store your test strips in a cool dry place and do not let them get damp.
The accuracy of the readings will deteriorate quickly after the use-by date printed on the pot, so always check that the test strips are in-date prior to use.