Lovibond Phenol Red Test Tablets Comparator for testing the pH of your swimming pool, spa or hot tub water. The pH of your pool or spa water should be between 7.2 to 7.6 in the pH range. This will ensure your pool or spa water is ideal for your chlorine to work properly and ensure bather comfort. Use these Lovibond Phenol Red Test Tablets in Comparator test kits only. With the new blister strip, the user just pushes the tablet through the protective foil, straight into the sample. Simple, time-saving and practical.This type of packaging, long established in pharmaceutical applications, combines all the advantages of protective foil, with convenience for the user. Each tablet is contained within an individually formed foil cup, lined with the latest aluminium composite material, and guaranteeing product performance. These Phenol Red Test Tablets are manufactured by Lovibond and all Lovibond Test Tablets have a minimum of 5 years before their expiration date. Storage & Handling - Store in a cool, dry place away from oxidizing and reducing agents, strong acid, alkalis, solvents and organic materials. - 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. Lovibond Code: 511750BT