i use 2 15w tubes n a fan for seedlings n keep the light a 1/2 inch from the top of the plants for 2 weeks,you dont need alota light for seedling stage just get it close ,n i agree with pink on the light cycle ,ive found my seedlings are happier when they get a few hours of sleep with no light no fan each night,i use 20/4
but everyone has their own ways .good luck


get that light down on them !