Please help me guys. I want to make Water Control Level with 2 board node-MCU and control with blynk. The first board for the water level sensor and the second board for the relay on the pump. I found it difficult to program the pump system to be automatic when the water runs out because it uses two boards. does anyone have the same project as me or knowen the program?
look at bridge widget 
if distance is not big, i offer radio transmitter to relay. Also nrf24|01 with antenna may be useful. I control my remote devices with nrf transmitter. It can send data around 2 kilometers in open air.