sera Test NOł 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 ?