MrStinkyanswered grow question 3 years ago it is all about managing your ppfd and DLI - if you are delivering say 300-320ppfd thats alright, if you are delivering 650ppfd that is definitely not cool for a seedling and you're gonna have a bad time, m'kay?
I would say use 1 until they are mature enough to take another light, otherwise you might quickly waste β¬25