There are about 600 kilograms of Epsom salt in a float tank, and like any form of salt, it can sting on a freshly waxed or shaven body. However note that Epsom salts can be used to heal skin conditions like psoriasis; the first 7-10 mins may be uncomfortable, You can ask at reception if they supply a single-use pack of petroleum jelly that acts as a liquid bandage, alternatively, you can bring your own.