Water is an essential element for survival. In many parts of the world, there seems to be a water crisis due to population growth. However, action must be made to obtain usable water. To some extent, wastewater treatment is an excellent solution to address this problem. Wastewater treatment, like other household appliances, is essential for reusing waste water. A lot of wastewater treatment facilities are large, expensive, and energy-intensive. The most efficient way to deal with the aforementioned issue is through a sequential batch reactor, a space-efficient reactor. Many controllers are used to control the Sequential Batch Reactor (SBR), Even though many controllers are in usage, their price prohibits the use of SBR at every home. In an effort to use a compact and cost effective Atmel microcontroller is used and also proved that. Based on the experiments, the Atmel microcontroller performs best without reducing the treated water efficiency. It is found that, the ultimate BOD and COD efficiency is 97.8% and 96.3%, respectively. Henceforth, it is suggested that the Atmel microcontroller can be utilized to regulate the small-scale SBR.