Nature & Environment
What is aquaponics - and how can fish poo help feed the world?
...resources, such as oil. [Trout fry in a tank] These trout fry could help provide the fertilizer to make chips... It begins with fish poo and pee, both of which contain lots of ammonia. Worms that live in rooting substrates break the solids down and then bacteria convert the ammonia into nitrate, which acts as a fertiliser. The plants absorb the nitrate and effectively...