I need to use a light soil for my first 2 weeks of veg , the final pot with heavy soil is 7 lts . What would be a good size for the first pot to endure the first 2 weeks ?
that sounds about right. i used to here people useing the for the first two weeks of growth. so nigh on half a liter. sounds right but no harm will come of .25ltr
like bob said start with the cup make sure u put holes in the bottom of it for drainage, then you can move to a 1gal pot for veg a couple of weeks, then from there 3 to 5 gal pot for flower and finish....