DIY is awesome and you should do it because it's not as hard as it sounds and is pretty cool. (And cheap!)
But if you want something really easy, have you considered some of the liquid fertilizers sold by say RootMedic or PFertz? With such a tiny tank that dollar goes a lot further and this way it doesn't have to be "crazy": just pump a few times and forget about it for a day or three.
Also, I think NY has some clubs. Maybe one of the members there can help out or measure out a mix for you that you can dilute in, say, a 2L bottle, then dose a bottle cap every other day or something.