sera Test NO³ nitrate for the exact determination of the nitrate content in fresh and marine water. The test is sufficient for approx. 60 tests. Nitrate is the final product of nitrogen-containing pollutants. Nitrate levels above 50 mg/l are not only harmful to the fish but also strongly promote algae growth. Thus, the nitrate level should be checked regularly by means of the sera nitrate-test.Do you have questions about this article ?