Effect of bacterial additives on the performance of septic tanks for wastewater treatment in the Upper Egypt rural area

The experimental work was executed on 6 septic tanks represent two modified types located in villages of the Upper Egypt. Three of them receiving waste with medium organic load, while the others receiving waste with high organic load. Mixture of five selected, adapted, enzyme active producer, bacillus bacterial species has been used as additive to the septic tanks under investigation in order to test its ability to improve the effluent quality as well as increase the efficiency. Regarding the septic tanks receiving the medium load, a slight improvement in the effluent wastewater quality was achieved few days after the addition of the bacteria. At the 6 th