Relax – 1kg – Granular Shock Treatment


Hot Tub / Spa / Swimming Pool Chlorine Oxidiser


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Granular Shock Treatment – Relax 1 Kg

  • Granular Shock Treatment from Relax is a fast dissolving and easy to use chlorine shock treatment for swimming pool water eliminating bather wastes, contaminants and algae
  • The high chlorine content of Relax Granular Shock enables you to quickly establish a chlorine level in your pool water
  • These non-stabilised chlorine shock granules are ideal for commissioning new swimming pools or regular oxidation of swimming pool water
  • The 1 kg Tub has dosing rates and full directions for use on the packaging

Once a fortnight, or more frequently in hot weather, the pool water should be shock treated by the addition of granular shock.

Also apply this product if algae growth has appeared on the walls or floor of the pool or there has been an exceptionally high level of bather load.

Instructions for using Relax Granular Shock:

  1. Maintain pH levels within the ideal range 7.2-7.6. If the level is not in this range, adjust. Maintain free chlorine residuals within the range 1 – 3 mg/l (ppm).
  2. Add product at a rate of 110g per 10m3 of pool water.
  3. Pre-dissolve granules in a clean plastic bucket filled with clean, warm pool water, at a maximum rate of 100g of product per 2.2 gallons / 10 litres of water.? Always add product to water, not water to product.
  4. Next, ensure that pool circulation pump is running before slowly pouring the solution immediately above the pool return.
  5. Never mix this product directly with other pool chlorine products.  Do not pour into a pool skimmer containing chlorine tablets.
  6. Never add this product when the pool is being used.  After treatment, wait a minimum of 30 minutes before using the pool.
  7. Wait until chlorine residual has dropped to 3 parts per million before allowing pool to be used.

Confused about your hot tub water chemistry? Our guides answer the most Frequently Asked Questions!

Why do I need to test my hot tub / spa / swimming pool water chlorine levels?

Why do I need to test my hot tub / spa / swimming pool water pH levels?

When do I need to shock my hot tub / spa / swimming pool water?

A genuine Relax branded product.


Relax 1Kg Granular Shock
– Directions for use –
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Why don’t you try our own brand instead

All of Castle Hot Tubs branded products are Grade ‘A’ quality – packed and labelled in the UK