I start with a lite mix of my amended soil (half promix) and put them into cups with real soil after a week or so. I use tea made of a little compost or EWC, molasses and probiotics and mycorrizhae to get the bacteria and fungi going good at three weeks. Usually before the flip I introduce the bloom nutrients to the tea. This time I'll be careful with adding too much nitrogen and will just go with the bloom nutes, molasses and probiotics. I add some myco once a month.