Backyard Aquaponics
A place to discuss aquaponics

Yes. Another method is to detect change in capacitance. This is mostly used for very low conductivity fluids or sluries from what i can see. I just have everything i need at home to make one with probes i think. Assuming i have the right opamp. Will just need some fiberglass resin to encapsulate it all.

rsev why do you know so much about flow meters ?
Looking foward to your attempt at making one. Don't be scared of the amplifier, if you don't want to build an opamp circuit you can get various monolithic instrumentation amps (or whatever).
You can also just use LTSpice and do a few simulations before you build the first amp proto...

Some notes to myself as future reference and for anyone interested.

http://new.aslo.org/lo/toc/vol_20/issue_2/0174.pdf

https://darchive.mblwhoilibrary.org/bitstream/handle/1912/3237/WHOI-74-21.pdf?sequence=1 - could be a winner? It is the unpublished manual mentioned in the above link. Has some great info, does not translate directly to what i had in mind but may translate well?

http://krohne.com/fileadmin/media-lounge/PDF-Download/Magmeters/HB_MID_e.pdf