I use a double 40 watt model of that for my reptiles. You have to have both tubes going at the same time or they don't work. They come in various sizes and I bought mine off trademe. They can be set for 10,12 and 14 hours on and rather than a time they stay on for the time you set from when you turn it on. I don't have it but I am sure there will be people on here with the knowledge to make one from parts. Cheaper--dearer--don't know.