Granular Shock (1KG) is a powerful chlorine-based shock treatment for hot tubs and swim spas. It’s ideal for clearing cloudy water should you be struggling with that, controlling algae, and dealing with heavy usage or periods of neglect.

For instance, if you haven’t touched your tub for a few months or you’ve been away, it’s a really good way to get it back to peak level. Alternative, if you have been getting a lot of use out of your spa, applying every two weeks or so is great to keep your water crystal clear.

This fast-acting formula quickly sanitises water, helping you enjoy a safe and hygienic spa experience without worry. While routine dosing keeps water clear, Granular Shock is especially useful after high usage, hot weather, or if the water has become slightly cloudy or algae is visible.

Using Granular Shock is simple. Pre-dissolve the recommended amount in a clean plastic bucket of lukewarm water, then pour it evenly into your spa while the circulation system is running. This restores proper water chemistry and helps maintain excellent water clarity, giving you a relaxing and worry-free hot tub experience.

Regular use as part of your hot tub care routine ensures your spa water remains hygienic, clear, and enjoyable for all users, including sensitive skin. You can host friends and family safe in the knowledge that your spa water will not only be warm and bubbly, but crystal clear too.

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1KG tub of Granular Shock chlorine
High-strength formula for cloudy water, algae, and heavy bather loads
Suitable for routine or occasional shock treatment
Dissolves quickly for even distribution
Ideal for regular hot tub maintenance and water care

Service Plan

Incorporating Granular Shock into your spa maintenance routine, along with test strips and regular chemical balancing, helps keep water clear, safe, and comfortable for every soak.

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Usage guidelines

Shock treat your spa once every two weeks, or more frequently in hot weather or after heavy use. After a period of neglect, it’s a good way to get it back up and running.

Adjust pH to around 7.2 using a pH decreaser or pH increaser before dosing.

Pre-dissolve the Granular Shock in a clean plastic bucket of lukewarm water, always add product to water, not water to product.

Slowly pour the solution evenly into your spa while circulation is running.

Keep the circulation system on until water clears.

For very poor water quality, double the dose.

Safety advice

Never mix Granular Shock directly with other chemicals, including chlorine tablets or cleaning products.

Handle in a well-ventilated area.

Use only the recommended dose, repeating treatment if needed.

Wash hands thoroughly after use and store in a cool, dry place to prevent dampening.

Why Use Granular Shock?

Cloudy water, algae, and heavy spa use can reduce your enjoyment and affect hygiene. Granular Shock provides a quick, reliable solution, clearing water and restoring safe, sparkling conditions.

It works alongside your regular hot tub care routine, helping you maintain proper sanitation, water clarity, and a stress-free, relaxing hot tub experience every time.

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