The data of adsorption kinetics of F-specific RNA bacteriophages Qβ and GA on drinking water biofilms under hydrostatic conditions was modeled. The rate limitation of virus adsorption was shown to be the free diffusion in water for GA where as another rate limiting step was demonstrated for Qβ. Modeling results also showed that the number of adsorbed viruses can be fitted with a limitless equation in static conditions. However sorption–desorption assays carried out in dynamic conditions showed that Qβ and GA phages have a similar affinity for the biofilm and reinforced that no significant virus desorption occurred during the first 10 h of adsorption from a bulk containing virus in static conditions. The small surface properties variations between the two phages do not induce significant differences of their adsorbed quantities in hydrodynamic conditions but they significantly affect the rate at which adsorption occurs in hydrostatic conditions.