super noob light question

Hi there I'm using CFL's on my seedlings (small vegging plants?) I'm gonna get a HID soon and
I"m a bit confused about something I know I can't but a 400w bulb in a ballast approved for 250
but can I put a 250 bulb in a 400w ballast lamp? If I get a 1000w ballast can I use bulbs less than that? say a 400w (cause of heat and stuff)

I think I want to use 250 or 400 cause my closets small but if in the future I expand it'd be cool to not have to get another ballast lamp.

get a 400w lumatek switchable ballast u can put a 250 in there if u turn it all the way down or u can get a 400 and dim it down to 250

for sure. any digital ballast (in my experience anyway) will allow you to use different bulbs. set the switch to whatever the wattage of the bulb is and away you go. Even if you have mine on 400w setting with a 250w bulb, it simply wont switch on until you correct the settings. idiot proof.

digital ballasts... worthy investment ! way less freakin heat as well ime

Digital Ballasts are nice if you want to pay a lot more than a standard iron core ballast. I use iron core, the transformer gets hot, like 60 celsious. Just use the right transformer with bulb, man