Nitrogen cycle in aquarium
Legend: (1) Addition of food and nutrients, (2) Production of urea and ammonia by fish, (3) Ammonia is converted to nitrites by beneficial nitrosomonas bacteria, (4) Nitrites are converted to nitrates by beneficial nitrospira bacteria. Less toxic nitrates are removed by plants and periodic water changes. (5) Evaporation. (6) Light. (7) Soil. (8) O2 produced by plants. (9) CO2 produced by fish.
Source
Boundless vets and curates high-quality, openly licensed content from around the Internet. This particular resource used the following sources:
"Aquarium-NitrogenCycle."
http://commons.wikimedia.org/wiki/File:Aquarium-NitrogenCycle.svg?uselang=he
Wikimedia
CC BY-SA.
