my grow closet set up any tips would be appreciated

Hi im new to growing this year.Ive tried to read and learn as much as i could but im still not 100% on everything yet. All i got is a closet to grow in its 3ftx5ftx7ft. i was planning on buying a Hydrofarm Sunburst 400W Hortilux Hp sodium Plant grow light system. I also plan on getting the Sunburst cooling fan system to reduce some of the heat in the closet. As for the strains i chose i picked at nirvana seeds. i decided to go with feminized seeds because i wasnt sure if i trusted myself trying to determine if the plants are male or female yet. i pick the strains swiss cheese, white rhino, and short rider. could anyone help me with my set up or give me tips about what types of plant food to use, lighting times, how many plants i should grow at a time in the 3x5x7 area.

I'd start off with 20 plants in 6" pots(about 7.5 sq feet), assuming you're starting from fem seed. This way you can sex them, and have plenty of room for the females from the space you recoup by culling males which will be about 20-25%, typically. Leaving you with about 15, or 1 plant per sq foot(SOG), so you should develop a thick canopy.

Plants are really easily to tell sex. Males typically show first, but not always. Often hermies will show sooner as well, but can develop at any time. There are plenty of examples a search away.

A full spectrum nutrient can be highly beneficial, that's one with more than solely NPK. Vegging it's better to go with a high N fertilizer, perhaps higher K, otherwise PK can be the same, with solely a higher N. Fish emulsion, bat guano, manure, urine, etc. Ratios of 3:1:2, 3:1:1, or 3:2:2 are good.

Flowering you want a higher P, perhaps a higher K, and a lower N, otherwise N and K can be the same. Bone meal, rock phosphate, manure, etc. Ratios of 1:3:2, 1:3:1, or 2:3:2 are good.

Light periods: 18/6 from seed throughout vegetative. 12/12 for flowering.