Agreed. I would just say to make sure they get 4 weeks veg min. Im one grower who likes to veg longer so I can have some big plants, you need good clearance and remember some strains will double in size during flowering.Depends on many factors. Some people veg for a while to get bigger plants/yields. Some go 12/12 right away to harvest sooner. Size of containers/res, number of plants and amount/type of lights will play a role too.