Blue Horizons Calcium Hardness Raiser – Rapidly increase calcium hardness


Supplied in 5kg and 25kg drums, Blue Horizons Hardness Raiser is a calcium flake which rapidly increases calcium hardness to the desired level.


Blue Horizons Calcium Hardness Raiser

Key Features

  • A calcium flake which rapidly increases calcium hardness
  • Part of the B.O.A.S.T. System

Ideal calcium hardness level: min. 200mg/l (ppm)

Incorrect calcium hardness

Low – Corrosive water/Etching of surfaces – Add: Calcium Hardness Raiser

High – Scale formation/Rough surfaces/Cloudy Water/Reduced circulation – Add: Stain & Scale Inhibitor

Application Instructions
1. Before applying this product, it should be pre-dissolved in a clean plastic container at a maximum rate of 100g of product per 2.2 gallons (10 litres) of clean cold water. Stir well to ensure the product is fully dissolved.
2. Add the resulting solution to the pool, near the inlets with the filtration system running.
3. Following the application, the pool water may become cloudy, so keep the filtration running continuously until the water clears.
4. Repeat application to achieve the total dose required. It is recommended that the total amount is split into three equal doses with a minimum of 8 hours between each.
5. After application, check the pH level and if necessary, adjust.

Litres           Gallons                   To increase CH by 10mg/l               To increase CH by 25mg/l
4,546            1,000                                           68g                                                     170g
11,365           2,500                                         170g                                                     425g
22,730          5,000                                        340g                                                     850g
45,460        10,000                                        680g                                                    1.7kg
68,190         15,000                                           1kg                                                  2.55kg

Warning: Heat is generated when pre-dissolving this product. Always use clean cold water.

Used for increasing the calcium hardness of pool or spa water.

Calcium hardness is the measurement of dissolved calcium in the water.

For Pools, calcium hardness should be maintained at a minimum of 200mg/l (ppm) as low calcium hardness can damage the pool and its equipment, therefore, it is vital that the level is kept above the minimum using Calcium Hardness Raiser.

Water that is too soft has even known to lead some swimming pool tiles becoming loose.  This happens as the tile bonding cannot work effectively in these conditions.

To ensure calcium deposits do not form, it is vital to check pH levels regularly.


Additional information

Weight N/A
Pack Size

5kg, 25kg

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