6-Way Test Kit for Free Chlorine, Total Chlorine, Bromine, pH (acid demand), Alkalinity (DPD)
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. As with all perishables, reagents are sensitive to environmental influences and will last longer under controlled conditions.
The manufacturer recommends the following:
Store in a place where the temps do not fluctuate as it will cause deterioration. Keep temp range between 36°–85°F
Keep out of direct sunlight. (Note: their brown plastic bottles help protect very light-sensitive reagents.)
Be careful not to expose to air and humidity--replace caps immediately and tightly
Do not switch bottle caps or bottles as this can cause contamination. Do not touch test strip pads.