Nitrate Test

Look for light yellow →

Photo by Hal

Nitrate is made in the aquarium by the biological filter. Beneficial bacteria in the biological filter convert wasteful ammonia and nitrite into nitrate. A high nitrate level indicates a build-up of fish waste and organic compounds, resulting in bad water quality and contributing to the chance of fish disease. Excessive

Nitrate also gives out a nitrogen source that can stimulate algae growth.