In a large square tank was the water that he is allocated from the Nile channel that supports the area. He is given water every second day. Years ago they had problems with mosquitoes breeding in it, and it turned dark green with algae and smelt bad. Someone suggested fish, so he put some in. Every year they harvest two big catches of Nile perch. We all watched fascinated as two men climbed into the water (fully dressed) and proceeded to set up a net with a long straight rod on each end. They caught twenty large fish in about ten minutes, throwing dozens of small ones back.