The API aquarium water test bundle includes both a nitrate and nitrite test kit to help aquarium owners closely monitor water quality. The nitrate kit tests for levels from 0-160 ppm and comes with 90 tests, while the nitrite kit measures 0-5 ppm nitrite and includes 180 tests. Both freshwater and saltwater aquarium owners can use these easy-to-use test kits. By regularly testing for nitrates and nitrites, invisible water problems that endanger fish health can be prevented. Excess nitrates encourage algae growth and organic pollutant accumulation, while high nitrites inhibit respiration and suppress immune systems in fish. The color-coded tests make it simple to detect unhealthy levels so aquarium water can be changed or treated before fish are harmed. With 60 years of experience creating aquarium products, API provides both kits in this bundle to complement complete water testing. The combination ensures aquarium water stays balanced and safe for all types of fish. Responsible testing and maintenance are made convenient with these kits.