This base unit provides water supply and volumetric measurement to other experimental accessories. Molded fiberglass bench-top into an open channel and measuring tank with space for mounting accessories. Fiberglass main storage tank with drain valve. Circulating pump. Stepped measuring tank for measurement of high and low flow rates. Level indicators for water level in open channel and measuring tank, Bull's eye level for correct level reading. Variable area flow meter (optional). Bench mounted on lockable wheels.