I always used to soak my harps in water. It did cause the wood to swell, but I really loved the dirty sound that came from soaking them, but they wore out faster. I didn't car because that was back when you could get a Blues Harp for about $7 - $8 dollars. A friend told me that I should have soaked then in a glass of Vodka..works the same bu doesn't ruin the reeds. He carried a small flask of vodka with him to the gigs and used the same over and over...adding a little each time the level got low. A lot cheaper than buying a glass at the bar.