Scotsman water filters can extend the life of your Scotsman ice machine and improve the taste and quality of your ice. The AquaPatrol Plus filters leave the chlorine in the water to keep the ice machine cleaner longer. The Polyphosphate Feed inhibits any scale build up and prevents any slime building up in your ice machine or ice bin. Scotsman water filters are easy to install and maintain and should be replaced every 6 to 12 months.