water tank gauge

[nj_m715]

I paid 40 bucks for a gauge, it's the wrong size and I need to stick my head out my window to see it
this is cheaper and can fit any size tank, for a few extra dollars you build it into a small project box or old tick tack container etc
I'd add a momentary push button to save power like many rv's

[RWS]

Yes this will do any size tank.  Transistors are probably PN2222.  The water conducts to the wire connected to the transistor base (green) turning on the transistor.  Just make the wire the length you want.  You are not limited to 4 wires.  You could have 6 or 8.  If you take the transistor base up to about .5Vdc it will turn on (conduct) from emitter to collector.  Boy it's been a long time.....

[John Galt 1]

Now that's a neat idea.

[nj_m715]

here's the one I bought, my tank is couple feet taller so the gauge reads empty when a few hundred gallons are still left

it's still a good gauge for the right application, just not for me
I'll  build an electronic gauge on some rainy day

https://www.amazon.com/Atlantic-Water-Gardens-Harvesting-Systems/dp/B005HJ9F0U/ref=pd_sim_86_5?_encoding=UTF8&pd_rd_i=B005HJ9F0U&pd_rd_r=0cd1d0b4-15bd-11e9-855f-d167bec0427b&pd_rd_w=sPFq3&pd_rd_wg=ah0uj&pf_rd_p=18bb0b78-4200-49b9-ac91-f141d61a1780&pf_rd_r=SZNMA42GWGJG0CFTXFAQ&psc=1&refRID=SZNMA42GWGJG0CFTXFAQ