By Sarah MorlandMEXICO CITY, July 31 (Reuters) - Hundreds of Mexican hotel workers, tractor operators and specialized Navy personnel are heading out to the beach each day at dawn to clean record masses of rotting sargassum seaweed off pristine Caribbean coastlines around popular tourist resorts. The displaced seaweed turned into a self-sustaining belt that rides on ocean currents to northern Brazil and through the Caribbean, bringing masses of algae onto Caribbean island nations, the popular Riviera Maya and into the Gulf of Mexico. "It's a balance because offshore sargassum is a natural habitat and there's tons of turtles and fish that live among it," Barnes said. "So if you try and sweep the Caribbean clean, you're going to have ‌a lot of collateral damage." The state government of Quintana Roo, meanwhile, plans to expand ​a biofuel plant in Cancun.