Biological treatment process in wastewater treatment plants relies heavily on MLVSS/MLSS ratio as a key indicator of microbial activity and treatment efficiency. However, the accumulation of inorganic solids, particularly fine sand, reduces this ratio, impairing system performance. Hydrocyclones offer a promising solution for grit removal due to their compact design, high separation efficiency, and operational simplicity. This study reviews the principles and applications of hydrocyclones in wastewater treatment plants, emphasizing their role in enhancing the MLVSS/MLSS ratio by selectively removing inorganic particles while retaining organic matter. Key factors influencing separation efficiency are discussed, along with case studies demonstrating improved sludge quality and energy savings. Findings suggest that hydrocyclones can significantly remove grids and improve MLVSS/MLSS ratio. Hydrocyclone desanding is viable alternative to conventional sedimentation, especially in plants with space constraints or high influent grit loads.