ESP8266 Community Forum

Hello all please suggest a good cost effective water level sensor for interfacing with arduino for overhead tank around 7feet, had googled and came to know about ultrasonic sr04t sensor but do suggest cheap option as well as it has to be used in number of water tanks(around 5) and in low budget initially.. thanks for your guidance

It depend if you need to know the actual level, or just want to know if the level is too low.
if you just want a low level warning, have a look at the optical water level sensor

If you need a Non-contact Tank Water Level Sensor See This or this for a lower cost version
If you need to know the actual level, you could build your own Ultra Sonic Water Level Sensor