Environmental DNA (eDNA) is increasingly used to survey marine biota, but requires validation against visual methods to understand biases in both approaches. We developed and tested a rapidly deployable platform combining water sampling for eDNA with wide-field stereo-video imagery, and compared fish assemblages inferred from this system with interspersed baited remote underwater stereo-video (stereo-BRUV) samples. The platform simultaneously collects stereo-video, oceanographic data and multiple water samples across diverse habitats and depths to 600 m, and was demonstrated in a no-take zone of Ningaloo Marine Park, Western Australia. Integrating visual survey data with eDNA estimates increased detected fish diversity by ~6.5% compared to eDNA alone, and revealed significant differences in assemblage composition between methods. The demonstration underscores method-specific biases and complementarity, and highlights the need for eDNA metabarcoding advances to resolve abundance and life stage, and to relate eDNA data to imagery-derived abundance, length, and habitat information.