Nitrate test kit for freshwater/saltwater aquariums. 90 tests. Fast, easy and accurate. Reads 0 to 160 mg/L or parts per million (ppm) of nitrate. Child resistant safety caps. This Kit contains: Two dropper bottles for accurate dispensing of test solutions Easy-to-read instructions and color chart Non-staining glass test tube with snap-tight cap. Nitrate buildup in aquariums is often an indicator of declining water quality. High levels of nitrate are frequently associated with poor fish health, algae growth, and a build-up or organic pollutants. This kit measures nitrate (NO3) in freshwater and saltwater aquariums. The enclosed instruction booklet will tell how to test for nitrate, what the results mean and how to improve water quality and fish health.