This looks very cool!

I've just been looking at your github repository, you mention you use the HV7360 chip to generate the ultrasound pulse.

I'm slightly confused by the datasheet for this chip, am I right in thinking you supply +/- 100V to this chip? If so, what are you using to generate that voltage out of curiosity?

(I have a ~2MHz ultrasound transducer which I keep meaning to play with, to attempt to measure liquid density, so your project is very interesting to me!)