Bathtub
A stock-and-flow sandbox: the tap is the inflow, the drain is the outflow, the water is the stock.
Water
0.0 L
Inflow
0.0 L/s
Outflow
0.0 L/s
Net
0.0 L/s
Spilled
0.0 L
Empty
Last 60 seconds
Water (L, left axis)
Inflow (L/s, right axis)
Outflow (L/s, right axis)