Kerasal Foot Therapy Foot Soak makes your feet look and feel better after just 1 soak. This foot soak soothes irritated skin and achy feet and helps to soften rough skin, leaving your feet looking and feeling clean and healthy. Made with natural tea tree oil, this soak features Epsom salt with skin restoring nutrients. This skin care foot bath hydrates and softens as it cleanses and works as a deodorizer for intensive, therapeutic foot care. Fill a basin or foot spa with warm water and add the crystals until they dissolve. Soak your feet in the Epsom salt bath for 15 to 20 minutes.