Aquaponics what is it? - The simple answer is it's combination of aquaculture and hydroponics . Water from the fish tanks is pumped through the grow beds which are filled with gravel or some other inert growing medium.  The plants growing in the grrowing medium extract the nutrients from the water (made from fish poo). The water then returns to the fish tank cleaned and freshly oxygenated.

My first aquaponics system

 My second aquaponics system