Did you not get the Booklet that came with the tower? It really does explain the "process" ...
- For the initial Germination in the Rock wool, after putting the seeds & top with vermiculite in the wool, you leave them in a Tray with about 1/4" of water, cover, and allow to germinate. Just keep an eye on them to make sure there is 1/4" water until you put them in the Tower. After they sprout, you move them to a sunny spot. continue to maintain 1/4" water until a good set of roots appear out the bottom of the wool. (You can add diluted Nutrients to this at this time. I just take a little out of my Tower tank & add it tot he seed tray.)