Wave energy convertors have the potential to generate a sizeable proportion of Ireland’s energy needs. Such platforms will be susceptible to bio fouling over their design life with marine growth capable of altering the hydrodynamic loading. Marine growth causes member effective diameter, mass, drag coefficients, force and hydrodynamic added mass to increase. In this paper, marine growth of various thickness and surface roughness is numerically modelled on two torus shaped point absorbers moving against a monopile in operational conditions using combined potential flow boundary element method and Morison equation viscous drag. Marine growth thickness and surface roughness have a notable effect on the platform hydrodynamic forces. However, the power matrix remains generally similar. The smaller WEC shows the greatest change with a 20 % increase in draft and 5 % increase in power.