Cylinder solid control system has attractive appearances. The system was patent products designed to cope with drilling operations to be performed in tropical areas. The system has been applied successfully in Venezuela. With suction ports and sand-discharging ports located at the bottom of the tank, 100% of drilling fluids can be feed and discharged. At the same time, design of the system can facilitate sand-removal and collection of drilling fluids. Application of the system can electively minimize environmental pollution. All tanks are closely located without pass way in between, which can facilitate installation and dismantle of these tanks.