A medical waste fluid collection cart may include a container assembly and a suction tube having a lumen extending through the suction tube. The suction tube may communicate with the container to deposit waste fluid from a surgical site in the container. The container assembly may include a container, a base forming a bottom of the container, and a lid assembly. The base may include an interior surface defining a draining opening. The interior surface may extend along a ramped path toward the drain opening. The lid assembly may include a lid ring and a lid capable of engaging each other with a twist lock mechanism. The lid ring may engage the container and the lid may cover at least part of a central opening to the container. The container may have a window and a tinting assembly. The container assembly may have a vacuum level detection system.