1st timer,problems with light

Hello everybody,I am new here,but I need some help. I have read a couple of books about growing,i tried three times outdoors with very good results. now I want to try indoor. my tent is 1,2x1,2x2m,one 600watt mh bulb,and one 600 watt Gib lighting flower spectre xtreme-200000 lumens. and I have all the other parts-filter,balast,reflector-ajust a wing and etc. my question is-when the seeds sprout out from the pots,I know that I have to put them under the MH light,but what must be the distance between the light and my very little plants,and when I have to move down the light,and in flower stage what is the normal distance between HPS light and my plants. I saw some graphics of MH and HPS lights for this distance,but I want help from someone with experience. THANKS A LOT,and can you recommend me some seeds,which are easy to grow,and don't need many space to grow,I want to put 10 plants inside my tent...THANKS A LOT AGAIN

generally as long as you can comfortably put you hand under the light your good. seedlings and freshly rooted clones a little higher, too much light can do more harm then good.

Thank you,tulow,but can you tell me what must be the distance when they sprout out(between my little plants and 600watt mh light). is 2-3 foot too much or enough,and when to start moving down the light. every day several inches till I reach 18-24,or must I move it only one time to reach 18-24???