Photo credit: Sabi Asma (Togo) Description: Sabi Asma and Abdel Rahman El Gamal (Founder of the website)
The structure shown in the corner of a fish pond in the inserted picture is typically used in the organic manuring in Togo as well as in other African countries. Instead of spreading the organic materials over the entire water surface, it is placed within the crib whereas the decomposition takes place and the nutrients are filtered between the bars of the crib and with the water current in the pond, the whole pond is fertilized.
This simple system is usually adopted in small-scale fish farms where farmers rely on organic manure. While only the nutrients dissolve into the water and used for the fertilization, the undissolved bulk of the manure remains within the crib and hence could be easily moved without disturbing the entire pond water.