In all the five experiments sludge was first added in the reactor and left for warm up for 24 h. On the next day the slaughterhouse waste was added and then it was left for 5 days for acclimatization. Sample was collected for analysis. After the collection of sample more slaughterhouse waste was added. On the tenth day another sample was collected for analysis, followed by the addition of the slaughter- house waste. On the fifteenth day the last sample was collected for analysis. The addition of sludge (inoculum), slaughterhouse waste, and water in each experimental run is presented ( Table 1 ).