A water level gauge with built-in barometric pressure compensation is the bluetooth equivalent of the U20L: MX2001

which has both battery and solar panel solutions

A four-channel thermocouple LCD display data logger to measure and record temperature

blir dataloggern mycket smidig när man ska tanka ur data ur loggrar som installerats i svåråtkomliga utrymmen

HOBO UX100-014M Thermocouple A water level gauge withA four channel thermocouple LCD display data logger to measure and record temperature, with an internal sensor to log ambient temperature. Requires HOBOware software and a USB cable (cable included with purchase of HOBOware on USB stick).