Help & Advice

You can find in this section technical support guides and information to help you get the best out of your pool or spa. Read our Help & Advice here


Troubleshooting problems in swimming pools and spas. Read our FAQs here

Fast Delivery

Delivery is FREE for all orders over the value of £75.00 and £10.99 for orders under this value to mainland UK. Read more about our delivery policy here

Pool Size Calculator

Knowing your pool's volume is vital when making adjustments as all calculations and dose rates are based on it.

View Pool Calculator

Excellent Reviews

See what our great customers are saying about us on Truspilot.

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Terms & Conditions

Conditions of Use

Please read these conditions of use carefully. If you proceed to use the site, you are agreeing to these rules. Definitions: "Products" means the products described in any order made via the Oninepoolchemicals website. "Site" means the current live version of the Onlinepoolchemicals website as maintained on the world wide web.

1. is the online store of Water Treatment Products Ltd.

2. and its contents are designed to comply with UK laws and regulations. Water Treatment Products Ltd makes no representation that any information contained in this Site is relevant or appropriate to other locations.

3. This Site offers you the option of viewing information about Onlinepoolchemicals products. If you choose to view this information you are accepting that Oninepoolchemicals is supplying this information at your individual request for information.

4. Use of this Site is at your own risk. Neither Water Treatment Products Ltd nor any other party involved in creating, producing or delivering the Site is liable for any direct, incidental, consequential, indirect or punitive damages arising out of your access to, or use of, the Site. This includes damages to, or viruses that may infect your computer equipment. Without limiting the foregoing everything on the Site is provided to you "as is" without any warranties or merchantability, fitness for a particular purpose, or non-infringement. Please note that some jurisdictions may not allow the exclusion of implied warranties so check your local laws.

5. The copyright to the contents of this Site belongs to Water Treatment Products Ltd. Users may download materials for their own personal, non-commercial use, provided all copyright and other proprietary notices are kept intact. The copying, redistribution, re-posting, publication, adaptation or alteration of any part of this Site for any public or commercial purposes is prohibited without written prior permission from Water Treatment Products Ltd.

6. The trademarks, logos, characters and service marks (collectively the "Trademarks") displayed on the Site are registered or unregistered trademarks of Water Treatment Products Ltd. Nothing contained in this website should be construed as granting, by implication, estoppel or otherwise, any license or right in and to the trademarks without the express written permission of Onlinepoolpoolchemicals Ltd. Your use of the Trademarks and contents of the Site, except as provided in these Conditions of Use, is strictly prohibited. You are advised that Water Treatment Products Ltd.

7. Water Treatment Products Ltd will enforce their intellectual property rights in the Site and its contents to the fullest extent of the law, including seeking criminal sanctions.

8. Images of people or places displayed on the Site are either the property of, or used with permission by, Water Treatment Products Ltd. The use of these images by you is prohibited unless specifically permitted by these Conditions of Use or by specific permission elsewhere on the Site. Unauthorised use of images may violate copyright, trademark, privacy and/or publicity laws as well as communications regulations and statutes.

9. Technical information provided on this site is for guidance only. Before making any changes to your pool you should check with the pool installer that it is suitable for your pool.

10. Personal information voluntarily submitted to Water Treatment Products Ltd via the Site may be used by Water Treatment Products Ltd.

11. Any communication or material which you transmit to Water Treatment Products Ltd through this website or otherwise via the Internet will be treated as non-confidential. Any communications and other material which you send to Water Treatment Products Ltd and shall remain the property of Water Treatment Products Ltd and may be used for any purpose whatsoever, commercial or otherwise without compensation.

12. This Site may contain links to other Sites. Water Treatment Products Ltd is not responsible for the content of any other Site or for on-going review of other Sites. The inclusion of any link to such Sites does not imply endorsement by Water Treatment Products Ltd. Your linking to any other Sites is at your own risk. Hyper-linking to this Site, in any manner, may not be permitted without Water Treatment Products Ltd’s written permission.

13. Water Treatment Products Ltd does not represent or warrant that this, or any Site to which ours is linked, will be accessible or available on a timely basis, or that access to the same will be uninterrupted or error free.

14. Water Treatment Products Ltd reserves the right to cancel orders whereby the customer address does not match the delivery address. Water Treatment Products Ltd also reserves the right to request clearance of payment prior to dispatching goods in the form of a bank transfer.

15. It is a crime to use a false name or a known invalid credit card to order. Anyone caught willfully entering an erroneous or fictitious order will be prosecuted to the fullest extent of the law. We track the electronic "fingerprints" of every order placed on to enable us and all legitimate crime prevention and prosecution authorities to trace individual users engaging in criminal activities on our website.

16. Water Treatment Products Ltd reserves the right to modify these terms at any time without prior notice. Any modification of these terms will be deemed to be effective from the date and time of posting on

17. Water Treatment Products Ltd attempts to include accurate and relevant information on this Site, but cannot undertake to encompass all such data. It assumes no responsibility for any errors or admissions in the content of the Site.

18. only sells products of the very highest quality and we are convinced that our products are the best available.

19. This site, and the conditions above, are governed by the law of England and Wales. The courts would resolve any disputes arising from this site.