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Zodiac Calcium Down Scale & Stain Control 1L – Pool Chemical (DG)

Calcium hardness treatment for reducing scale and staining caused by high calcium levels in pool water.

- 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.

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

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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

WPQCHD1

$35.00

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Product Description

Reduce Scale and Staining from High Calcium Hardness

Zodiac Calcium Down helps manage high calcium hardness in pool water, reducing scale formation, staining risk and cloudy water caused by elevated calcium levels. It supports clearer water while helping protect pool surfaces, heaters and salt chlorinator cells from calcium build-up.

High calcium levels can make pool surfaces feel rough and cause scale to form on equipment that works hard every day. By keeping calcium in suspension, Calcium Down helps maintain better water balance in pools affected by hard source water, mineral water or ongoing calcium build-up.

Features & Benefits

Reduces scale from high calcium hardness: Helps decrease scale formation caused by elevated calcium levels in pool water.
Helps reduce staining risk: Supports stain prevention by helping keep calcium and trace metals in solution.
Supports clearer water: Helps prevent cloudy water linked to high calcium hardness.
Helps protect pool surfaces: Reduces conditions that can cause rough scale build-up on pool surfaces.
Helps protect equipment: Supports scale control in heaters, pipework and salt chlorinator cells.
Compatible with common pool sanitisers: Can be used in pools with standard sanitising systems.

Dosage & Coverage

Calcium Down Dose: 1L chelates calcium and can reduce the calcium hardness reading by approximately 100ppm per 40,000 litres of pool water.
Frequency: Reapply as needed to maintain the desired result. As a guide, maintenance dosing may be required approximately every 5 weeks.

Important Usage Information

Always test pool water before dosing and follow the product label directions.
Aim to keep Calcium Hardness within the ideal range for your pool surface: 200–300ppm for most pools, or 150–250ppm for fibreglass pools.
Calcium Down helps hold calcium in suspension. It does not permanently remove calcium from pool water.
If total hardness is above 800ppm, check whether the pool is a mineral pool or whether bore water or hard source water is contributing to the reading.
Contains phosphonic acid, which can elevate phosphate readings. Do not treat phosphates at the same time, as this may reduce the effectiveness of Calcium Down.
Temporary changes in water colour or clarity may occur during application. Water clarity should return once treatment is complete.

This product is classified as Dangerous Goods. Handle with care, avoid contact with skin and eyes, and keep out of reach of children.

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

Does Zodiac Calcium Down remove calcium from the pool?

No. Calcium Down helps chelate calcium and hold it in suspension, which can reduce the calcium hardness reading and help control scale. The only true way to physically remove calcium from pool water is by dilution with fresh water.

Why is high calcium hardness a problem?

High calcium hardness can contribute to scale formation, cloudy water and rough pool surfaces. Scale can also affect heaters, pipework and salt chlorinator cells, making equipment work harder over time.

Why did my water colour or clarity change after adding Calcium Down?

Temporary changes in water colour or clarity can occur during treatment, especially when calcium levels are high. Continue filtration and monitor the pool as directed. Water clarity should return after the treatment process is complete.

Can Calcium Down affect phosphate readings?

Yes. Calcium Down can contribute to phosphate readings. If you are also managing phosphates, avoid treating both issues at the same time.

What should I check if total hardness is above 800ppm?

If total hardness is very high, check whether the pool is a mineral pool or whether bore water or hard source water is contributing to the result. In some cases, dilution with fresh water may be needed to physically reduce calcium content.

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

Specifications

More Information
SKU	WPQCHD1
GTIN	9343609024758
Barcode	WPQCHD1
Brand	Zodiac
Model	WPQCHD1 - Calcium Down 1L Bottle
Product Type	Pool Chemical
Shipping Type	Standard
Chemical Type	Balancers
Chemical Function	Calcium Down, Scale Inhibitor / Scale Stop
Active Constituents	Hydroxyethylidene Diphosphonic Acid Complex: 370g/L

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.

Zodiac Calcium Down Scale & Stain Control 1L – Pool Chemical (DG)

Pool Supplies & Equipment

Quality Pool & Spa Equipment

Best warranties and support

Renowned Brands

Worry-free purchases

30 Days Satisfaction Guarantee

Hassle-free

Free, Easy Returns

Satisfaction Guarantee

Terms

How to return a product

Use coupon 'NOW' for 10% OFF

Reduce Scale and Staining from High Calcium Hardness

Features & Benefits

Dosage & Coverage

Important Usage Information

A Better Pool Experience Starts with the Right Chemistry

Frequently Asked Questions

Does Zodiac Calcium Down remove calcium from the pool?

Why is high calcium hardness a problem?

Why did my water colour or clarity change after adding Calcium Down?

Can Calcium Down affect phosphate readings?

What should I check if total hardness is above 800ppm?

Shipping

Returns

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