Taylor Technologies liquid swimming pool test reagent R-0005, Acid Demand Reagent (for 2000 Series). For use as directed with Taylor Technologies test kits. R-0005 is used in combination with R-0004 for the acid demand test.
All reagents have a shelf life, whether they are liquids, powders, crystals, tablets, or test-strip pads. If kept dry, powders and crystals are very stable; acids are also long lived. Date of manufacture is not the controlling factor when it comes to shelf life – storage conditions are more important.