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Zodiac pH Down Dry Acid pH & Total Alkalinity Reducer 25kg – Pool Chemical

Dry acid pool balancer that lowers high pH and Total Alkalinity, helping chlorine work effectively while supporting comfort and scale control.

- Satisfaction Guarantee: If you are not satisfied with a product for any reason, you are welcome to return it to us for a full refund or exchange within 30 days of the purchase date - even if you have used the product. Returns are free, and we will cover return shipping.

Pool Supplies & Equipment

Quality Pool & Spa Equipment

Our products have been selected because of their quality and we are confident that you will be pleased with your purchase.

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Renowned Brands

We only supply products from renowned brands that offer comprehensive manufacturer's warranties and offer service and support.

Worry-free purchases

30 Days Satisfaction Guarantee

You are welcome to return any product for a refund or exchange. See terms below.

Hassle-free

Free, Easy Returns

Returns are free, there are no fees. We also make sure returns are easy to organize and processed promptly.

Satisfaction Guarantee

We stock quality pool and spa equipment and supplies from the most renowned manufactures in Australia and the world and we are confident that you will be very pleased with your purchase. If for any reason you are not satisfied with a product, you are welcome to return it to us for a refund or exchange within 30 days of the purchase date. The refund will be issued to the full amount paid for the product including shipping.

Terms

You must contact us within 30 days of the date of purchase.
The product must be returned in good conditions.
Products damaged because of incorrect use, negligence or misuse will not be accepted.
All components, accessories and original packaging must be returned.
A copy of the original receipt must be included with the return.
Products must be shipped or returned to our Penrith NSW warehouse using a pre-paid label we will supply.

If you have any questions about our return policy, please contact us on 1300 766 619 or through our "contact us" form.

How to return a product

For more details including the steps required to return a product click here

In stock

SKU

WPQDA25

$120.00

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Product Description

Controlled pH for Better Pool Water Balance

Zodiac pH Down Dry Acid is used to reduce high pH and Total Alkalinity in swimming pool water. Keeping pH in the correct range helps pool water stay more comfortable, easier to manage and better suited to everyday sanitising.

High pH can make chlorine less effective and may contribute to scale-forming conditions. This dry acid format offers a practical alternative to liquid acid, with no liquid acid fumes and easier measuring, storage and handling.

Features & Benefits

Reduces high pH: Helps bring elevated pH back toward the recommended swimming pool range.
Reduces Total Alkalinity: Helps lower Total Alkalinity as part of acid-based pool water balancing.
Supports chlorine performance: Correct pH helps pool chlorine work more effectively.
Helps manage scale conditions: Lowering high pH helps reduce water conditions that can contribute to scale.
Dry acid convenience: Easier to measure and store than liquid acid, with no liquid acid fumes.

Dosage & Coverage

To reduce Total Alkalinity: 150g per 10,000 litres decreases Total Alkalinity by 10ppm.
To reduce pH above 8.2: Add 200g per 10,000 litres.
To reduce pH 8.0–8.2: Add 120g per 10,000 litres.
To reduce pH 7.8–8.0: Add 60g per 10,000 litres.
Frequency: Test pH weekly and adjust only when required.

Important Usage Information

Always test pool water before dosing and follow the product label directions.
To lower pH with less effect on Total Alkalinity, dissolve first and apply evenly around the pool edges.
To lower Total Alkalinity with only a slight effect on pH, pour the dissolved dose slowly into one spot in the deep end.
Do not overdose. Low pH can be corrosive to pool surfaces, fittings and equipment.
Do not mix with other pool chemicals.

Ideal pH range for swimming pool water is 7.2–7.8.

A Better Pool Experience Starts with the Right Chemistry

Zodiac pool chemicals support the key parts of everyday water care, from balance and sanitising to algae prevention, clarity, stain control and equipment protection.

Each product has a clear role in helping pool water stay cleaner, more comfortable and easier to manage, so the pool feels ready to enjoy more often.

Frequently Asked Questions

Should I use pH Down differently for pH and Total Alkalinity?

Yes. For pH adjustment, dissolve the product and apply it evenly around the pool edges. For Total Alkalinity adjustment, pour the dissolved dose slowly into one spot in the deep end.

Why should I retest before adding more pH Down?

Acid can continue to affect water balance as it circulates. Retesting helps avoid overdosing, which can push pH too low and make pool water corrosive.

Is Zodiac pH Down the same as pH Down Tablets?

No. This product is dry acid in granular form for general pH and Total Alkalinity adjustment. Zodiac pH Down Tablets are a separate tablet format with different application benefits.

Why is dry acid often preferred over liquid acid?

Dry acid is easier to measure, transport and store, and it does not give off liquid acid fumes. It still needs careful handling because it can cause serious eye damage.

What happens if pH is allowed to stay too high?

High pH can reduce chlorine effectiveness and make scale more likely to form. Regular testing helps correct pH before it creates larger water balance problems.

How should pH Down be stored?

Store pH Down in a cool, dry, well-ventilated place with the container tightly closed. Keep it protected from moisture and away from other pool chemicals.

Image shows product in new packaging design. Actual product received may vary while previous label design is being sold through.

Specifications

More Information
SKU	WPQDA25
GTIN	9343609025564
Barcode	WPQDA25
Brand	Zodiac
Model	WPQDA25 - pH Down 25kg Flexi Pack
Product Type	Pool Chemical
Shipping Type	Standard
Chemical Type	Balancers
Chemical Function	Alkalinity Down, pH Down
Active Constituents	Sodium bisulphate: 1000g/kg

Documentation

Shipping & Returns

Shipping

Same-day dispatch applies to orders received by 12.00 pm (AEST) during business days. Orders received after 12.00 pm and on weekends or public holidays will be dispatched on the next business day.

Delivery fees are $19.95 flat-rate per order Australia-wide, no matter how many products are in it. Orders containing bulky items like sand filters, acoustic boxes, heat pumps, pool covers, and pool slides may incur additional fees as they require specialized carriers.

Below are the estimated time to arrival in business days once an order is shipped.

Destination	Sydney	NSW	VIC	QLD	SA	WA/NT
Business Days	1 - 2	2 - 4	2 - 4	2 - 4	3 - 4	5 - 6

Rural and remote addresses, where delivery is not provided every day, may take longer.

Returns

- Satisfaction Guarantee: If you are not satisfied with a product for any reason, you are welcome to return it to us for a full refund or exchange within 30 days of the purchase date - even if you have used the product. Returns are free, and we will cover return shipping.

We take full responsibility for the safe arrival of the products that you order from us. We will replace at our expense any product that arrives faulty, damaged during transit, or is the incorrect product. Click here for details

If you have any questions about our shipping policy or our return policy, please contact us on 1300 766 619 or through our contact us form.