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OPC Fast Dissolving Shock Granules 450g

This Item
Essential Extras
£3.99 £8.99
Product ID:
In stock
  • Unstabilised Chlorine
  • Ideal For Shock Dosing (Deep Clean)
  • Perfect for Swimming Pool, Spa and Hot Tub Water
  • Rapid Dissolving
  • Kills Bacteria and Viruses
  • CLP Product Information Sheet 
View All Product Details Here

OPC Fast Dissolving Shock Granules 450g

`A weekly shock dose is essential to ensure clean and healthy pool water`

Ideal for Shock Dosing the swimming pool water on a weekly basis after heavy bathing or as a preventative measure to ensure bacteria and organic contaminants are eliminated.

Rapid Dissolving Un-Stabilised Chlorine Shock Granules are ideal for raising Free Chlorine readings without having an impact on stabiliser reads (cyanuric acid).


  1. Test the water with a chlorine test kit to determine the free chlorine reading
  2.  Ensure bathing has ceased before adding chemicals to water
  3.  Adjust pH to 7.2
  4.  Ensure filtration is on (pump running
  5.  Broadcast the contents evenly over a wide area in the deepest part of the pool. 
  6. Test the water the following day. Bathing should not re-commence until the free chlorine level is 4.0 mg/l (ppm) or below.
  7. To keep the pool water in pristine condition, repeat this procedure once every fortnight.

Storage & Handling

  • Store in a cool, dry place.
  • Contact with combustible materials may cause fire.
  • Do not mix with other chemicals.
  • Always wear suitable gloves and eye protection when handling.

Use biocides safely. Always read the label and product information before use

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