Here, we introduce the deposition of CNx on low density hollow glass microspheres (HGM), which enable floatation in aqueous media, and couple this composite with a benchmark noble metal H2 evolution co-catalyst (platinum; HGM/CNx|Pt) as well as noble-metal-free nickel phosphide (HGM/CNx|Ni2P). We demonstrate that such floating PR composites can be easily recovered and reused over ten consecutive PR trials using realistic illumination conditions and pre-treated model wastes including pre-treated biomass (cellulose) and plastic (PET). We also track the change in PR activity in both co-catalyst systems and show the advantage of floating materials in turbid waste environments in, to the best of our knowledge, the largest areal-scale PR system reported in the literature to date. Floating photocatalyst composites offer a practical method for efficient use of precious metal co-catalyst and scaling PR without loss in areal activity in a solar-light driven process.