A sag flow loop may include: a test section; a pump configured to at least pump fluid containing particles suspended therein at variable rates through the sag flow loop including the test section, the variable rates inducing formation of a bed of particles settled out of the fluid in the test section; and a flow meter densitometer configured to measure density of the fluid flowing through the sag flow loop. The sag flow loop may be configured to determine a sag of the particles in the fluid. The pump, the flow meter densitometer, and the test section may be connected via flowlines. The sag flow loop may have a volumetric capacity of less than four liters.