Those seelings look really healthy, they aren't quite ready for needing fertilizer yet. For most plants thats at about the 4-6 week point. Yeah if you are in coco definitely want some nutrients going on.
My germination mix which is peat moss based has about a cup of composted chicken manure and 1/4 cup dolomitic lime in.
My germination mix which is peat moss based has about a cup of composted chicken manure and 1/4 cup dolomitic lime in.