Biological sulfate and thiosulfate reduction can help clean up waste from certain industrial processes. Researchers found that using sand as a carrier for the microbes can increase their concentration and improve the rate of waste treatment. The microbes attached to the sand particles, with some bacteria helping convert hydrogen into useful compounds. The community of microbes on the sand was similar to those in the liquid, but some types were more abundant on the sand. Overall, attaching the microbes to sand boosted their effectiveness in reducing sulfate and thiosulfate in the waste.