The Qguai 9 in 1 Aquarium Test Strips are perfect for testing the pH, nitrate, nitrite, carbonate, chlorine, alkalinity, iron, copper, and hardness levels in your saltwater or freshwater aquarium. These strips are easy to use and provide accurate results in seconds. With a wide range of applications, these strips are perfect for testing the levels of all sorts of products in your aquarium. The Qguai 9 in 1 Aquarium Test Strips are also placed dry at 2 degrees Celsius to protect from light, and the validity period is 24 months.