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Iluka Hardup Calcium Hardness Increaser 500g – Spa Chemical

Name: Iluka Hardup Calcium Hardness Increaser 500g – Spa Chemical
Brand: Iluka
SKU: 53HU500G
Price: 26.00 AUD
Availability: InStock
Rating: 90 (2 reviews)

Rating:

90% of 100

Effectively increases Calcium Hardness in spa water, helping bring hardness back to the correct level.

- 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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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.

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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.

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In stock

SKU

53HU500G

$26.00

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Product Description

Bring Low Calcium Hardness Back into Range

Iluka Hardup effectively increases Calcium Hardness in spa and hot tub water, helping return hardness levels to the correct range when readings are too low.

Water that is low in calcium can corrode equipment, etch concrete and grouted surfaces, and create conditions that may favour algal growth. Hardup helps correct low Calcium Hardness so your spa water stays properly balanced within the Iluka Sea Minerals routine.

Features & Benefits

Increases Calcium Hardness: Helps raise Calcium Hardness in spa and hot tub water to the correct level.
Equipment Protection: Low calcium levels can contribute to corrosion of spa equipment and components.
Surface Protection: Helps reduce conditions that can etch concrete and grouted spa surfaces when calcium levels are too low.
Water Condition Support: Helps correct low-calcium water conditions that may favour algal growth.

How to Use

Test the spa water with a suitable test kit to measure Calcium Hardness.
Calculate the required dose according to your spa volume and test result.
Dissolve the required amount of Iluka Hardup in a bucket of water first.
Add the dissolved solution directly to the spa water.
Allow the water to circulate before re-testing.
Repeat only if further adjustment is required.

Dosage & Coverage

Calcium Hardness Dose: Add 10g per 1,000 litres of spa water to increase Calcium Hardness by 10ppm
Frequency: Use when Calcium Hardness testing shows levels need to be increased

Important Usage Information

Dosages are intended as a guide. Always follow the dosage instructions on the product label.
Dissolve in a bucket of water before adding to the spa water.
Never add Iluka Hardup via the skimmer, as this product releases heat while dissolving and may damage the skimmer basket or housing.
Always add chemicals to water, never water to chemicals.

Calcium Hardness should be maintained between 200–275ppm for concrete and tiled spas and hot tubs, and between 175–225ppm for other surfaces.

The Iluka Sea-Mineral Spa Experience

Iluka is an Aboriginal word meaning “near the sea”, and the feeling of being in a sea-like environment is at the heart of the range. Iluka Sea Minerals by Lo-Chlor brings together mineral comfort, water clarity and simple spa care to help create a more natural, luxurious and enjoyable spa experience.

Inspired by the calming feeling of being near the sea, Iluka transforms spa care into something softer, fresher and more rewarding — less like maintenance, and more like a calming ritual.

Frequently Asked Questions

Why does Calcium Hardness matter in a spa?

Calcium Hardness helps keep spa water properly balanced. If calcium levels are too low, the water can become more aggressive and may contribute to equipment corrosion, etching of concrete or grouted surfaces, and water conditions that favour algal growth.

What Calcium Hardness level should I maintain?

For concrete and tiled spas or hot tubs, maintain Calcium Hardness between 200–275ppm. For other surfaces, maintain it between 175–225ppm.

Why can’t I add Hardup through the skimmer?

Hardup releases heat as it dissolves, which may damage the skimmer basket or housing. Dissolve the required amount in a bucket of water first, then add it to the spa water.

Can I use Hardup in all spa and hot tub types?

Yes, Hardup can be used to increase Calcium Hardness in spa and hot tub water, but the target range depends on the surface type. Concrete and tiled spas require a higher Calcium Hardness range than other surfaces.

How do I know if Hardup is needed?

Use a Calcium Hardness test kit. If the result is below the recommended range for your spa surface, Hardup can be added to raise the level.

Specifications

More Information
SKU	53HU500G
GTIN	9312113022970
Barcode	LCC-50-91022
Package Length	7 cm
Package Width	7 cm
Package Height	20 cm
Brand	Iluka
Model	Hardup 500g
Product Type	Spa Chemical
Shipping Type	Standard
Chemical Type	Balancers
Chemical Function	Calcium Up
Active Constituents	Calcium chloride: 1000g/kg

Reviews

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.