الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Aquaculture is one of the world’s fastest-growing industries for providing food which is expanding daily. Egypt is the seventh-largest aquaculture country in the world and the major in Africa. In order for Egypt’s aquaculture business to thrive in the future, it is essential to address problems like resource usage disputes, energy, production of fish seed, cost, availability of quality feed and marketing and trade. The most important challenge in Egypt is in the sustainability and management of its water resources. The main reasons for water sarcastic crisis are increasing demands and bad management techniques So, Water resource preservation is absolutely essential and must be done in all ways limit waste and impose severe regulations on the discharge of industrial wastewater into water resources. The majority of water loss in Egypt occur in aquaculture due to water exchange cycle which maintain the farming water quality. Typically, the most significant water quality factors in aquaculture are dissolved oxygen (DO), unionized ammonia (NH3), nitrite, nitrate, total alkalinity, total hardness, and pH. In aquaculture, High stock density of tilapia has a great effect on water quality due to the significant increase in the amount of ammonia in pond water. For this reason, Fish are stressed, which raises the possibility that they will get sick. The most nitrogenous waste that tilapia excrete is Ammonia which produced from the protein catabolism, immediately and gradually produced into the water by fish gills from the blood. Ammonia can cause chronic and acute hazardous effects even at relatively low doses. immunity and growth of tilapia may be lowered by high ambient ammonia concentrations leading to fish death, besides massive financial losses for aquaculture.