light during seed starting??

ok i germinated my seed, planted them and are in humdity dome under grow light how long do i need to keep my lights on or do i need light right

Read the FAQ titled How to Grow Marijuana- Basics. It will pretty much answer everything you just asked.

I would go max 18. Also watch for any sign of mold on the leaves or in soil the high humidity of the dome creates the perfect environment for mold to grow. If you havent already go get a temp and humidity gauge I got my last one for 3 bucks. Don,t let your humidity drop below 65-70 % and be careful not to over water dont want to drowned your roots. Plants look thirsty when the are dying from root rot