setting up first room

im planning on getting a 4x4x6 tent and pair that with a 400w mh/hps ive done some reading and alot of people recommend a 600w for the size but i cant go with 600w i was wondering how many plants i should go with this is my first grow attempt and not sure how many plants i should go with for better yield with a 400 i was thinking of 2x 10gal totes with 6-8 plants each and keep them relatively small........or would it be simpler/eaiser for 3-4 bigger plants?

also would like to know what a few good strains would be for that size area/new grower

any takers?

I read northern lights are easy for newbie green thumbs.

You want to crack all the seeds you can, then flower a lot of small plants from clone; 4 per square foot would do