Is this lamp enough for 2 of sativa or not? Give me please some knowledge of yours. This is first time I'm planting somthing

You will need a HPS for flowering, MH is (best) for veg. Don't mix autos and photoperiod plants together.............your photos won't flower at 18/6 and your autos won't produce well at 12/12. 600w will be plenty.

bwahaha, shit.. equal halves if pushing utmost area covered... for 24 sq ft you'll want some minimal overalp in center to reduce any low-light areas. you want a more even blanket across the canopy, if possible.

if you do push a larger size****, spread bulbs a bit more too. make it cover equal halves and that will dictate how far apart

sorry, tapped send on accident... 1200/50 = 24 sq ft of coverage, give or take... with single point of light you'll have much hotter spots directly under it vs along edges of that area. Since you have 2 bulbs, don't do a circle.. do a rectangle or oval coverage since you have 2x1 formation of bulbs. Maybe 3.x feet by 6+feet that adds up near 24-25 sq ft. You can probably push further out but eventually it will make a noticeable impact on desnity of nugs. This suggeston is for providing a near max DLI to an area... you can probably still get good buds by pushing area a little larger but anything approaching 150% larger than 24sq ft with 2 600w MH HID bulbs is spreading the amount of light too thin and larfier/airy buds will be more common / higher proportion of total.

they are photoperiods, so how large they grow is totally up to you... fill at least 1/2 the space before flipping to 12/12 light schedule (causes bloom phase). They should double in size after that before they start focusing 100% on growing teh flower/buds. i'm not well-versed on teh MH stuff, but you probably want 50w/sq ft. 1200 / 50 =