those plants are way to young for any nutes. Just feed with strait ph adjusted water dont give any nutes till they are about a month old or have at least 2 sets of fan leaves. Feeding nutes now will only stunt growth. When you do start feeding nutes i suggest getting a tds meter for peice of mind. Start out with about 300-400ppm and work your way up by about 100-200ppm per week.iwouldnt go any higher than 1200ppm in veg. 900ppm is standard strenght for most strains but you can push higher just do it slowly