Disadvantage of visual observation of particle layer sediment on the vessel bottom by classical Zwietering's concept can be eliminated by new application of the electrochemical method for observation of particle layer sediment on the vessel bottom and for identification of just off-bottom particle suspension state. This paper deals with principles of application of this method and evaluation of signals from electrodiffusion probes. Results of signal analysis illustrate very well the applicability of the electrochemical method for this purpose.