I got the idea. It's probably too early to even be adding anything to the water but they did respond really well to it, it's just that 1 drop (vitamins and amino acids) was meant for 4.5 liters (apprx. 1 galon) and there is no way I will use that much water anytime soon in a single watering.
About a week ago I prepared some water with nutes and now it's been sitting around for a few days and I'm wondering if it's still a good idea to keep watering with it. It's my first grow and all the clones seem to be doing ok, except one of them which for some reason has huge, fully developed...