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On one end you want to have a chemical stock tank in a one liter bottle hooked up to a computer controlled peristaltic pump. The pump will meter in the chemical at a set rate to a 4 L tank that has a pressure sensor set up at the bottom to record the height of water. For part of the experiment you want to meter in the chemical (without drainage), however for another part of the experiment you do not want to meter in the chemical. For another part of the experiment you want to be able to drain the tank while adding in more chemical.
In your drawing, you can indicate a peristaltic pump as a circle inside of a square, a chemical stock tank as a bottle, a solenoid valve with an X and tubing as a straight line. Try to draw the pressure sensor as it appears.
Click here to see how closely your schematic matches this one.
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