Keeping your spa water properly balanced is essential for a safe and enjoyable hot tub experience. Our pH Increase (5KG) treatment is designed to raise low pH levels in pool, hot tub, or swim spa water when test results show acidity is too high.

When pH drops below the recommended range, water can become uncomfortable for sensitive skin/eyes and may even corrode metal components inside your spa system. Low pH can also reduce how effectively chlorine sanitises the water.

Using pH Increase helps restore the ideal pH balance between 7.2 and 7.6, ensuring water stays comfortable, clear, and hygienic. Balanced water allows sanitising chemicals to perform properly while protecting your hot tub equipment from unnecessary wear.

This 5kg pack provides a long-lasting supply, often enough for up to a year depending on spa usage. By regularly testing your water with 3 Way Test Strips and dosing when needed, you can keep your spa water perfectly balanced and ready to enjoy. Alternatively, we also offer pH decreaser if your levels are too high. This is another good way to maintain both tub and water quality.

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5kg tub of pH increase granules
Designed to raise pH levels in spa or pool water
Helps maintain ideal pH balance between 7.2 and 7.6
Supports effective chlorine performance and water clarity
Long-lasting supply suitable for up to a year’s use

Nationwide delivery and professional installation service

Our certified engineers deliver and install hot tubs safely across the UK, including full electrical connections.

What's Included

Test your water regularly

Regular water testing helps maintain proper spa balance. Use our 3 Way Test Strips to check pH levels before each use and identify when pH Increase is needed to restore healthy water conditions.

Correct low pH levels

If pH falls below 7.2, add approximately 10g of pH Increase per 1000 litres of water. This gradually raises the pH level to a comfortable and effective range.

Pre-dissolve before adding

Always dissolve pH Increase in a clean plastic bucket of water before adding it to your spa. This ensures the treatment disperses evenly throughout the water.

Add with circulation running

Ensure your spa’s circulation system is running before adding the dissolved solution. Slowly pour the mixture near the return inlet, so it spreads evenly through the water.

Repeat until balanced

Continue testing your water daily and repeat dosing if required until the pH reading reaches around 7.4, keeping your hot tub water balanced and comfortable.

Safety notes

Never mix pH Increaser with other chemicals. Always add product to water, not water to product. Handle in a ventilated area, wash hands after use, and store safely in a cool, dry place.

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FAQs

Hot tub water care can seem confusing at first, but with the right products and guidance it quickly becomes simple. Our team is always on hand to help you maintain clear, safe water.

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