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BioGuard

BioGuard Shield 450g – Spa Calcium Hardness Increaser

BioGuard Shield 450g – Spa Calcium Hardness Increaser

Regular price $23.00 AUD
Regular price Sale price $23.00 AUD
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BioGuard Shield 450g – Spa Calcium Hardness Increaser

BioGuard Shield is a spa calcium hardness increaser designed to raise low calcium levels and help protect spa equipment and surfaces from corrosive water.

Correct calcium hardness is an important part of balanced spa water and works alongside pH and Total Alkalinity to help maintain stable water chemistry.

Why Use BioGuard Shield?

BioGuard Shield:

  • Raises low calcium hardness
  • Helps protect spa equipment from corrosion
  • Helps protect spa surfaces from etching
  • Supports correct overall water balance
  • Helps reduce problems associated with water that is too soft
  • Is suitable for routine spa-water balancing

What Is Calcium Hardness?

Calcium hardness is a measure of the amount of dissolved calcium in your spa water.

If calcium hardness is too low, the water can become aggressive and may contribute to deterioration of spa surfaces and equipment.

BioGuard recommends maintaining appropriate calcium hardness levels and using Shield when testing shows the level is too low.

When Should I Use Shield?

Use BioGuard Shield when a water test shows that your calcium hardness is below the recommended range.

BioGuard currently recommends a spa calcium hardness range of approximately 175–225 ppm in its spa water-testing guidance.

Always test your water before adding calcium increaser and dose according to your spa volume and current water-test result.

Low Calcium Hardness vs High Calcium Hardness

Low calcium hardness can contribute to:

  • Corrosion
  • Surface etching
  • Damage to equipment
  • Aggressive water conditions

BioGuard Shield is used to raise low calcium hardness.

If calcium hardness is already too high, do not add Shield. High calcium can contribute to scale and cloudy water and requires a different treatment approach.

How Much Shield Should I Add?

The amount required depends on:

  • Spa water volume
  • Current calcium hardness
  • Desired calcium hardness increase

Always follow the dosage instructions on the product label and make adjustments gradually.

Retest the water after treatment before making further adjustments.

Need Help Balancing Your Spa Water?

Pool & Spa World Tasmania offers free in-store water testing.

Bring in a fresh spa-water sample and our team can check calcium hardness, pH, Total Alkalinity and sanitiser levels and help determine the correct treatment.