Glad to hear they're doing good. :thumbsup:

Too soon for nutrients, per their size. Would give 'em another week or so before even thinking about nutrients. Have you downloaded and printed the Fox Farms weekly feeding schedule available from their website? If not, it's a good idea to do so.

Number of plants will likely be limited only by available footroom in the growspace, but I used to fit 6, 3 or 5 gallon pots under each 400w HPS. (I'm under CFL's for growth phase and 1000 watts of HPS for flower, now-a-days) But I'd do 'em all if you can fit 'em in the growspace. The longer you wait though...the harder it is to cull them. :jointsmile: