Mes researched zebrafish and carp as part of his Ph.D."We already know that zebrafish and carp use bacteria in their gills to turn toxicinto harmless nitrogen gas. Rather than excreting only ammonia after they eat, they turn some of it into nitrogen gas. This process is carried out by bacteria that live in the fish's gills. But we didn't yet know how they do that and what might facilitate it."looked at what happens when you change the way that the fish are fed.
Mes placed a pendulum in the aquariums, and when the fish swam up against the little ball at its end, they would receive a little bit of food."It takes less than a day for the fish to figure that out. Feeding them in this way reduces the amount of ammonia in the water."The bacteria that live in the gills of the fish act as a natural biofilter."It appears that the bacteria perform best when they're given small portions of food to process," says Mes.