Quick answer: Low pH can irritate skin and eyes while also stressing metal parts, seals and equipment. Adjust it gradually and watch alkalinity.
Low pH is sometimes overlooked because the water can look clean at first glance. Yet long-term acidic water can damage surfaces, metal parts and reduce bathing comfort.
What low pH can cause
The problem is not just a feeling. Low pH increases water aggressiveness, and in hot tubs the effect of heat and flow shows up faster.
- stinging eyes and skin irritation
- corrosion of metal parts
- damage to seals and components
- fluctuating disinfection
- unstable tester readings
How to proceed
Use pH-plus according to the instructions, let the water circulate and measure again. If pH keeps dropping, also focus on alkalinity.
- measure pH and alkalinity
- dose in smaller steps
- check more often in hot tubs
- do not use the water if it irritates the skin
When to look for the cause in the source water
If pH drops after every refill, the problem may lie in the source water or in low alkalinity.
Related guides
This article is original editorial guidance by Spa Pool News. For chemicals, electrical equipment and service work, always follow the manufacturer’s instructions and safety recommendations.
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