Just put together my Pro200 and added three feminized Northern Lightrs seeds. I put the seeds into the included grow sponges. 1 seed in each sponge (although aerogarden mentions putting more than one into each sponge, is this right?). They have been in there for about 19 hours with light. I just killed the lights on it. My main question is how long should the lights be on during germination? Thanks in advance, the information is always helpful.