Wastewater Treatment Optimization for Fish Migration Using Harmony Search

Table 1

Effluent water quality after wastewater treatment.

Treatment type	Effluent quality (ppm)
	DO	CBOD	NBOD
Secondary (settling + biological oxidation):	2	25	54
Secondary + filtration (microscreening):	2	13	50
Secondary + nitrification:	2	13	10
Secondary + nitrification + filtration:	2	7	10