Jacuzzi® Hot Tub Hardness Increaser - 1kg

Jacuzzi® Hot Tub Hardness Increaser - 1kg

Regular price £9.49

Unit price

only -1195 left in stock

Free 48-Hour delivery on orders over £50 within UK mainland - order by 3pm Monday-Friday. Find out more.

Features we love
  • Top grade calcium for hot tubs & spas with soft water
  • Prevents corroding of pipes and build-up of soap scum 
  • Get a cleaner and more comfortable soak
  • Prolongs the life of your tub and its components
  • Jacuzzi® premium quality you can trust
All about me

Our Jacuzzi Hot Tub Hardness Increaser is designed for use in hot tubs with soft water. It helps to raise the calcium levels, to maintain proper chemical levels to prolong the lifespan of your tub.

Hardness increaser helps prevent damage to the hot tub itself. When the water is too soft, it causes the plumbing to corrode or scale, which can be costly to repair. By raising the calcium level in the water, you can keep this at bay.

Harder water creates a more comfortable soaking condition, as well as preventing the build-up of soap scum on the walls and floor of your spa. Experience the Jacuzzi® difference for yourself.

How to use

Before adding to your hot tub, dissolve the hardness increaser in cold water, adding up 10g per 1 litre. Take care to stir well to ensure it’s completely dissolved, then add the solution to your hot tub while your jets are turned on.


What happens if water hardness is too low in my hot tub?

When your spa’s water is too soft, it causes the plumbing to corrode or scale, which can be costly to repair. 

How do I increase the hardness in my Jacuzzi?

If your spa’s calcium hardness level drops below the recommended 150 ppm, adding a hardness increaser to your hot tub is an easy way to balance levels.

If you need more information about managing your hot tub’s water, check out our balancing your hot tub’s pH level and total alkalinity guide.


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