Nitrates
What is it? Nitrates are a specific form of nitrogen that are formed after nitrites have been exposed to nitrifying bacteria. Nitrates (NO3) are bioavailable, meaning that they are an important source of nitrogen for plants.
Why is it important? Algae and other aquatic plants use nitrates as an important source of food. However, excess levels of nitrates in water can make it difficult for aquatic insects or fish to survive. If we do not manage the levels and understand the nitrogen cycle, algae growth can go unchecked and reduce the dissolved oxygen of the water. This directly impacts aquatic life.
What does it mean?
- Natural levels are usually less than 1 mg/L
- Concentrations over 10 mg/L will have an effect on the freshwater aquatic environment
- 10 mg/L is also the maximum concentration allowed in human drinking water
- For a sensitive fish the recommended concentration is 0.06 mg/L
- High levels could be caused by agriculture run-off