These genuine Water-ID DPD No. 3 photometer-grade tablets are the essential reagent for measuring total chlorine and combined chlorine (chloramines) in pool and spa water. Used in conjunction with DPD No. 1 tablets in the Water-ID PoolLab 1.0 photometer, they provide fast, accurate digital readings that go far beyond what a basic test strip can offer. Each pack contains 100 tablets, supplying a reliable stock of reagent for regular pool maintenance or professional use.<\/p>\n
Knowing your free chlorine level alone is not enough. Combined chlorine \u2014 the portion of total chlorine bound as chloramines \u2014 is responsible for the characteristic pool smell and the irritation of eyes and mucous membranes in swimmers. By measuring total chlorine with DPD No. 3 and subtracting your free chlorine (DPD No. 1) reading, you can calculate combined chlorine precisely and determine whether shock treatment is needed. DPD No. 3 tablets also play a role in ozone testing when used alongside DPD No. 1.<\/p>\n
First perform a free chlorine measurement using a DPD No. 1 tablet and record the result. Without emptying the cuvette, add one DPD No. 3 tablet and wait approximately 2 minutes for the reaction to complete before taking the total chlorine reading. Combined chlorine is then calculated as total chlorine minus free chlorine. Always perform the ZERO (blank) reference with sample water and no tablet before each test, and keep the light-protection cover in place during measurement for accurate results.<\/p>\n
Manufactured by Water-i.d. GmbH in Germany to photometer grade \u2014 the same standard required for the PoolLab 1.0’s precise optical measurements. Each tablet is individually sealed in an aluminium push-through blister (10 tablets per blister) to protect against moisture and contamination, ensuring consistent performance and a shelf life of up to 2 years. Store in a cool, dry place away from heat and direct sunlight to maintain reagent integrity.<\/p>","protected":false},"excerpt":{"rendered":"