water level controller through atmega8535

[deepakgupta.rf]

hello everyone,
i tried to make atmega8535 based water controller. in that 5vdc supply go to in water tank then level fill then wire gives 5 v supply to miconcontroller.
is it right method or shud use any intermediate ic in between micocontroller and water tank.
and in supply can be earth problem and can be tank earth problem
please resolve my problem

 

[bigdogguru]

I would not recommend directly connecting the wires directly to the ATMEGA.

Here are a few different approaches to water level detection probes and interface circuits:

Water Wave/Tide/Level Meter 2.0

BigDog