Here's a tip if you're lacking in sunlight, as we often are here during our gray West Coast winters. We put our sprouter trays on top of our radiator by the window. This way, they do get sunlight when it exists, but we've found that the moderate heat from the top of the radiator really helps get the sprouts going in absence of ample natural light.
Of course, this only works if you live in a cool old building and have radiators by your windows. ;)
In a gentle way, you can shake the world. ~Mahatma Gandhi