I am sure that you can, but I have never grown that way. Stinky, when she comes back around will be able to answer that better for you. I know that I have put molasses into a drip hydro reserviour (sp?) and it was fine. You just have to make sure that you pre-mix it in gallon jugs and shake vigorously so that you will not have a sticky build up in the bottom of your tank. It has to be dissolved first.
Good luck,
elway