Anyone interested in a discussion of artificial lighting? I have used artificial lighting for years starting with Metal Halide and High Pressure Sodium, then moving to T5 florescent, and most recently moving to LEDs. Great results with MH and HPS but the typical complaints of lots of exhaust heat and high electric demands. Full spectrum T5s have worked very well for the past 5 years. I have used the fixtures with 4 four foot tubes. I have found that the fixtures I bought had a higher failure rate than I like. The biggest problem was with the ballast failing after a couple of years. I have used LEDs for about 3 years now with hydroponics and 1 year with trees. I plan on replacing the T5s with LED as I go. I sued LEDs first with hydroponics and then with tropical trees. One observation with the LEDs versus the MH/HPS for hydroponics is that I can harvest the crop longer. Under MH/HPS the crop tended to grow rapidly and bolt in a couple of months. With LEDs that period is 3 to 4 months. The tropicals do well under LED. LED fixtures are still more expensive (initial cost) than the T5s; $250 versus $150. These fixtures work for a 3 X 4 foot footprint or larger. Although I noticed that the brand of LED I use just increased in price. To date I have bought Spider Farmer. I am not making a recommendation one way or the other. There are several sites that do side by side compares of the different manufactures.