Interactive sonification can provide a platform for demonstration and education as well as for monitoring and investigation. We present a system designed to demonstrate the facilities of the UK's most advanced large-scale research wave tank. The interactive sonification of water waves in the “ocean basin” wave tank at Plymouth University consisted of a number of elements: generation of ocean waves, acquisition and sonification of ocean-wave measurement data, and gesture-controlled pitch and amplitude of sonifications. The generated water waves were linked in real time to sonic features via depth monitors and motion tracking of a floating buoy. Types of water-wave patterns, varying in shape and size, were selected and triggered using wireless motion detectors attached to the demonstrator's arms. The system was implemented on a network of five computers utilizing Max/MSP alongside specialist marine research software, and was demonstrated live in a public performance for the formal opening of the Marine Institute building.