Cow dung, coming from a rumen animal is known to contain the native microbial flora that aids in faster biogas production. It has also been reported severally that cow dung is a very good starter for poor producing feedstock’s [23-25]. Figure 4 shows the gas production from cow dung. The average temperature of the digester was about 33.5ºC. It shows that the hydraulic retention time for cow dung is 40 days and gas production starts at the 5th day. Maximum gas is produced at the 26th day which is 0.0263 m3. Figure 5 shows the gas production in volume percent in four slots of hydraulic retention time. In first slot from 0-10 days about 10% gas is produced. From 11-20 days gas production increases to about 35%. In the third slot from 21-30 days the maximum gas is produced which is about 46%. Finally, from 31-40 days gas production reduces to about 9% and gas production ceases after the 40 day.