This study showed that growth retardation is unlikely to occur in
mediumand small-size Nile tilapia kept in nearly closed RAS. In fact, the
small individuals exhibited growth promotion instead of growth
retardation in nearly closed RAS. On the contrary, larger individuals
seemed to growfaster in theLOWaccumulation RAS. Therefore, it seems
that the accumulation of substances in the RAS affect differently small
and large individuals. As shown in Table 3,