Just add water. It's automatic, easy to use and costs only pennies a day to run. After adding the seeds, the sprouter delivers a continuous supply of fresh water and air to provide a simple, convenient way of growing fresh, tender and live sprouts in the convenience of your own home. Sprouts have a high concentration of proteins, vitamins, minerals, enzymes and maximum nutrition in a small package! It is suggested to change the water daily. FreshLife Sprouter is expandable to allow you to grow two times the sprouts! Just purchase a second sprout barrel from us to double your sprouting area. No other tools are necessary; just add the second barrel on top, place the seeds and plug it in...it's that simple! The expansion kit includes an extra barrel, top and bottom seed trays, the water tube assembly, and three stainless steel clips for support.