I have been using this hydroponic growing system for several years and find it very productive. It was simple and inexpensive to build. It consists of a tote from Wal-Mart, a small garden pump, six net pots, a scrap section of PVC pipe and short sections of tubing feeding each net pot. The cost to build this system was under thirty dollars, and it has produced several times its initial cost in salad greens. The romaine and waldman's lettuce has been growing in this system for only four weeks and is just about ready to harvest.