Unfortunately, there is no way to prevent salt buildup completely. There are ways to minimize it, though, making salt removal times less frequent and a breeze to do. The number one thing you can do indoors to help prevent excessive salt buildup is to water your plant properly every time. Take your plant outside or in a bathtub if possible; if not, use a drip tray. Water your plant with lukewarm water and water it thoroughly until you see excess water coming out of the drain holes in the bottom of your pot. After watering, allow your plant to drain and then expose excess water collected. Correct watering measures help filter salts that would otherwise be left to fester.