I have two of these sprouters. As I use fresh sprouts now and then, I felt that the two trays were not quite enough. It's handy to have the extra trays so that when my first seeds are two or three days in to germination I can start the next batch. I have grown alpha alpha, cress, radish, mung, mustard, and some others. I place both trays in the sink and steep for at least a couple of hours to start of a new batch. Then I drain the water away. Stack the trays on the green plastic drip tray. Leave in the day light. I then rinse at least twice a day, it only takes a minute. A good product.