Swimming Pool Chemicals - Blue Horizons Ultimate Winter Long Life Algaecide 5L

£24.95
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  • Blue Horizons Winter Long Life Algaecide
  • 5 litres treats up to 15,000 gallons
  • Copper free winter algaecide
  • Prevents staining & scale build-up
  • Compatible with Chlorine & Bromine treated pools
  • Free Winterisation Guide included
  • Part of the Blue Horizons BOAST system

Blue Horizons Ultimate Winter Time is a longlife copper-free algaecide formulated to prevent algae growth during the late autumn, winter and early spring in outdoor swimming pools. One dose will help prevent algae growth for up to six months. Ultimate Winter Time also helps to minimise the likelihood of stains and scale deposits during the closed season. Algae are microscopic plant life that can multiply rapidly in your swimming pool water in the right conditions. Recovering an algae infested pool can be time consuming and expensive which is why prevention is always preferable to cure. Our range of algaecides have been specially formulated to help you achieve sparkling clear and algae free water. We offer you a choice of weekly dosed and long life algaecides depending on your particular needs.

  • Blue Horizons Ultimate Winter Time - 5 Litres
  • The 5 litre container treats up to 15,000 gallons 
  • The longlife algaecide is an effective copper free winter algaecide which helps prevent the multiplication of most types of algae.
  • It helps to prevent staining and scale formation and is compatible with Chlorine, Bromine and Biguanide treated pools.
  • Part of the Blue Horizons BOAST system
  • Ensure pool water is clear and free from algae and debris before applying Blue Horizons Ultimate Winter Time.
  • Shock dose the pool water using Blue Horizons Granular or Rapid Shock (both available from our online shop) to achieve a free chlorine level of 10ppm.  
  • Gradually pour the required amount of Blue Horizons Winter Time Algaecide into the pool whilst the pump(s) are turned 'on', preferably near the water inlets to aid distribution.
  • Check the pH level and if necessary adjust to achieve the recommended winter pH range of 7.6 - 7.8
  • Keep the circulation system running until the algaecide is thoroughly distributed throughout the pool.
  • If the winter and spring are mild it may be necessary to periodically shock dose the pool water with chlorine. This will help keep the pool clear as the air temperature starts to rise.
  • A FREE pool winterisation guide will be sent with your order. 
  • Please see our winter pool guide for information on how to care for your pool during the winter, as well as information on other swiming pool chemicals to help you winterise your pool.
  • Guide Thumb

    How to treat green water

    Find out all you need to know about algae and green water, how to treat it and how to cure it.

Returns Policy


Your rights to return goods are protected under the EU Distance Selling Directive.

You are entitled to cancel your order and return the goods within 7 working days for a full refund not including the cost of delivery. Do this by contacting us by email or telephone and quoting the order number supplied to you. Your refund will be paid within 30 days. You are responsible for the cost and risk of loss or damage when returning the goods, so you should take out enough postal insurance to cover their value. This cancellation policy does not affect your rights when we are at fault - for example, if goods are faulty or incorrectly-described.

Exclusions: Bespoke items (made to measure items) are not included and cannot be returned. If a bespoke item is faulty then the product warranty /guarantee will take effect.

Any goods returned should be in saleable condition.

These terms apply to your order. We may change our terms and conditions at any time, so please do not assume that the same terms will apply in the future.

None of these terms affect your legal rights and these are not diminished in any way. If any term is held to be invalid under any applicable statute or rule of law, that term is automatically omitted from the terms to minimum extent necessary to comply with the law and without affecting the validity or enforceability of the remainder.

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