How do I use resistive strain gauge with potentiometric sensor to measure flow rate in a tank?

[Schid]

I have been working on a project but got stuck on how to use a strain gauge or spiral spring in conjunction with a potentiometric sensor to measuring the volumetric flow rate of water in a tank. I have successfully derived the area of the tank and the height, but the application/configuration of the above sensors is the issue.
I would sincerely appreciate any pointer or direction provided since I have been on this issue for weeks now.

 

[controlnovice]

School projects are not permitted on this site.

That being said: Strain gauges measure weight. Water weights 8.34 lbs/gal.

Take it from there.

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