I am researching the lifespan of Arduino sensors underwater. I want to measure the water quality of a lake using an Arduino. I have seen that turbidity, temperature, ph and conductivity sensors don´t last long underwater but I can´t find any research on google scholar about the possibles sensors for a 24/7 sensor underwater.
There are some sensors probes available that are robust and they can last up to 3.5 years underwater but the cost is very high. I want to know if there are sensors that can be underwater for long periods of time.