Your water can emit an odor if there's low levels of sanitizer, your pH is out of range, or there's bacteria or algae growth. For addressing this issue we will potentially need either dichlor chlorinating granules, pH Up, or pH Down. There's a possibility we may also need to flush the system completely, but first we should find out if our sanitizer or pH levels are the cause for the odor. pH levels are showing a little low, let's address this first before checking our sanitizer levels. Apply as many doses as it takes to get the pH balanced. Next, we'll check our total and free chlorine levels. Looks like our chlorine levels are low. Let's give it some chlorinating granules and see how we look afterwards. Just a friendly reminder, our pH levels should be between 7.4 and 7.6 and total alkalinity between 100-120 parts per million and chlorine levels between 2-4 parts per million. Now that our levels are balanced, should the odor continue, then we need to drain the hot tub, clean it, and fill it with fresh water.
For guided assistance check out our video on how to drain a hot tub and how to fill a hot tub. For more quick tips head over to our Quick Tip playlist. For more in-depth help with Master Spas features and functions check out our how-to for hot tub owners. And until next time happy hot tubbin.
For European countries, please refer to this Water Chemistry Guide for appropriate chemical levels per BS EN 17125:2018.