  The exceptionally long lifetime of surface nanobubbles remains one of the
biggest questions in the field. One of the proposed mechanisms for the
stability is the \emph{dynamic equilibrium} model, which describes a constant
flux of gas in and out of the bubble. Here, we describe results from particle
tracking experiments to measure this flow. The results are analysed by
measuring the Vorono\"i cell size distribution, the diffusion, and speed of the
tracer particles. We show that there is no detectable difference in the
movement of particles above nanobubble-laden surfaces, as compared to
nanobubble-free surfaces.
