I'm pretty new to this as well, so all I can say is what I've read and done.

I use nutrients every other watering, but I wouldn't start giving them any until they are a bit older, personally. For now I suggest simply soaking the soil thouroughly the first time, then water them with balanced water when the top soil is crusty and dry.

It's important not to over water them. Every few days is what I do.