The API Nitrate NO3 Test Kit is designed for use in freshwater and marine aquariums, providing 90 tests for monitoring nitrate levels in tanks up to 100 gallons. Made by API, a trusted brand in the aquarium industry, this test kit accurately measures nitrate levels to help maintain healthy water conditions for fish and other aquatic animals. The kit is suitable for all water types and is a reliable tool for ensuring proper water quality in your aquarium.