The best stuff to use is nickel safe ice machine cleaner. It comes in a little bottle and can be purchased at any appliance parts store or I think www.partselect.com has it also. Pour it in the water tray back where the pump is ( not the bottom of machine where the ice accumulates ) and put your machine in Clean and let it do it's thing. Also recommend having an in line water filter in the water supply to your icemaker if you don't all ready. Thanks for using justanswer.