Ambassador pH Minus (Dry Acid)
Quickly restore your pool's chemical balance with Ambassador pH Minus (Dry Acid), a fast-acting granular solution for lowering pH levels in swimming pools.
Available in 1kg sizes, or 5kg in our multipack sizes for a value-for-money discount.

Quickly restore your pool's chemical balance with Ambassador pH Minus (Dry Acid), a fast-acting granular solution for lowering pH levels in swimming pools.
Available in 1kg sizes, or 5kg in our multipack sizes for a value-for-money discount.

Ambassador pH Minus (Dry Acid)
Shop Ambassador pH Minus (Dry Acid) a fast-acting, easy to use solution for lowering pH levels in swimming pools. Ensuring swimmer comfort, protecting pool equipment, and optimising chlorine or bromine effectiveness.
What is pH Minus ?
Ambassador pH Minus (Dry Acid) is a fast acting granular chemical, used to lower high pH levels in swimming pools, when it becoms too high.
This pH reducer, it contains Sodium Bisulfate, which provides a safer alteranative to liquid acids.
Why Use Ambassador pH Minus (Dry Acid)?
pH Minus (Dry Acid) is essential to quickly and effectively bring high levels of pH down to a safe range, maintaining the correct pH level in your pool is essential for several reasons:
- Swimmer Comfort: A balanced pH is essential to prevent eye, nose and skin irritaion
- Chlorine Effectiveness: Chlorine works best within a pH range of 7.2 - 7.8 with 7.4 being ideal.
- Protects Pool Equipment and surface: Low pH can lead to corrosion and damage of metal parts, ladders and pumps.
- Safe and effective: The dry acid, granular formula is a lot safer to handle than liquid acids, prevents splash back when adding.
How to Use Ambassador pH Minus (Dry Acid)?
- pre-dissolve the dry acid in a bucket of water prior to adding it in to the pool, ensuring it is fully dissolved.
- Distribute evenly around the pool with the filtration system running, to spread it evenly.
- Wait 4 - 6 hrs before re-testing and adjusting measurements if necessary.
Dosage Guide
Add 50g per 4,545 litres (1000 gallons) of water.
Frequently Asked Questions
What Can Affect pH in my Swimming Pool?
Swimming pool levels are constanly changing due to a number of factors, so being aware of bthese factors helps to understand and maintain nalanced water levels.
- Heavy rainfall: Rain is naturally more acidic which can lower or affect your pH levels.
- Chemical Additions: Chlorine, shock treatments, and stabilisers can alter the pH balance.
- Seasonal Changes: With weather and temperaturs) especially in the UK fluctuating through seasons, weather status and outside temperatures can affect your pool conditions.
- Pool Usage: With heavy and busy pool usage, water changes from contaminents, body oils and products on personal using the pool
- Warm weather: Hot weather and high UV can lead to the chlorine and chemicals becoming lees or completely ineffective disrupting the chemistry of the pool.
How to Test and Adjust pH?
Regular testing ensures your pool water remains balanced:
- Test strips
- Photometers digital meters
- Test tablets
- If pH is too high, use Ambassador pH Minus (Dry Acid)
- If pH is too low, use Ambassador pH Plus (Alkali/Soda Ash)
Understanding Alkalinity and Its Role in pH Balance
- Alkalinity stabilises pH levels, preventing sudden changes.
- If alkalinity is too high, lowering pH becomes difficult.
- If alkalinity is too low, pH level can fluctuate drastically.
Need More Help?
For detailed guidance on pool chemistry and water treatment, we recommend reading the below 1st Direct Pools helpful guides:
- How Long Should You Wait to Swim After Adding Chemicals to a Pool?
- How to Prevent Algae Growth in Your Pool
- How to Balance Your Pool Water
- What Chemicals Do You Need for a Swimming Pool?
For more Product Specific Information Click Here
For further guidance, explore our resource section for downloadable documents or simply contact our technical team for expert advice.
| Restricted Product | Yes |
|---|

