Simple water level switch

Hi all,

I’m a newbie to this site, working for an engineering firm.

Context
I’ve built a working cooling system with piping, valves, etc.
The electrical side consists of a raspberry pi 3 with temperature sensors, a 8-channel relay with fish tank heaters to control the temperature of three seperate vessels depending on set-points.

Problem
I’m afraid of a leak somewhere and the level dropping too low and the heaters melting the vessels (did I mention they are plastic?)
So, I want to build a simple level switch, as seen in this schematic
I want to know, as I’m a rookie with wiring (did I mention I’m a chemical engineer and not electric/electronic), if this circuit will work.

Thank you in advance

The potential problem with this method is the purity of the water involved. If it is relatively pure, it won’t conduct when it hits (or in this case when it leaves) the sensor and you may not get an alarm. You would probably be better with a floating type switch like the ones listed here (although there still isn’t a Fritzing part that I’m aware of for one)

The float only depends on the water level dropping, not the purity of the water involved.

Peter