Diagram of the nitrogen cycle in an aquarium.
Original by <a href="//commons.wikimedia.org/wiki/User:Ilmari_Karonen" title="User:Ilmari Karonen">Ilmari Karonen</a> with translations into Hindi by <a href="//commons.wikimedia.org/wiki/User:Shypoetess" title="User:Shypoetess">Shypoetess</a>
2018-08-29
<a href="//commons.wikimedia.org/wiki/File:Aquarium_Nitrogen_Cycle.svg" title="File:Aquarium Nitrogen Cycle.svg">File:Aquarium Nitrogen Cycle.svg</a>