Algae and detritus co-occur on reef substrata, but their relative importance to consumers, in terms of biomass and nutrient content, is poorly understood. Epilithic algae, sediment and detritus were sampled among four windward zones at Lizard Island, Australia, using a vacuum sampler. This study examines the algal and detrital resources in the non-territory Epilithic Algal Communities (EAC) and evaluates their potential as trophic resources for grazing reef fishes.