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Someone told me that they found a very fine water mist nozzle somewhere that hooked up to their garden hose. They mounted it above the tub so the mist sprayed out above and fell down on those in the tub. He said the cool mist hitting you while sitting in the hot tub was great. I guess kind of like those cooling fans that they use on the sidelines at football games. I'd be interested to see if anyone else has tried this.