Study on the effect of some engineering factors on fish production under local

This study was carried out in Central Laboratory for Aquaculture Research and the World Fish Center to evaluate the effect of the different engineering factors on the water quality and growth rate of O. niloticus under local condition.The main objectives of the present study were:1- Comparing between two different shapes (rectangular & circular) and different dimensions (long rib & short rib) of ponds on water quality and growth rate of fish.2- Selecting the suitable aerators machine type (Agitator, Fountain & Vertical aerator) for the best water quality and fish growth rate.3- Evaluating the effect of different stocking densities on water quality and the growth rate of fish under different aerators machine that used. The experiment was conducted through two stages as .