When using iPS cells in 3D floating undifferentiated culture for regenerative medicine, efficient culture medium replacement is important. By stopping the mixing BioReactor for culture medium replacement, cells settle to the bottom of the culture tank having the ability of arbitrarily sticking together on the spot. This process results in uneven cell aggregation (sphere diameter), sometimes adversely affecting induced differentiation efficiency. When induced differentiation is the goal, single cells are discharged along with the culture medium, making it necessary to modify the inside of the culture tank so that they are not affixed to the surface. To satisfy these requirements, clogs must be avoided and culture medium discharge must be stabilized over a long period of time. A control system is an important part of maintaining continuous, precise culture medium replacement. The VMF-WSUB / TCS system has achieved these goals and features specifications that are capable of actual production.