I don't know about cfl's, 100w sounds small, but for 40 days that is waaaaaaaaaayyyyyyyyyy to small. Have you kept the 24/0 cycle the whole time? try 18/6 b/c we all gotta sleep sometime. Spend the little bit of money($50~) on a decent company brand organic(pure blend pro by botanicare is good) fertilizer, look for carbonate on the end of each ingredient(I.E. potassuim carbonate). You don't want to see anything else attached to the ingredients, like nitrate, iodide or chloride. One product that does use chealts (carbonate, nitrate, chloride) ingredients that aren't preferred is cns17(1-5-4) also by botanicare. It worked good for me if organic isn't your thing. If it is I'd suggest Great White for microbes. I'd use ZHO at transplant then switch to(for good reason) Great White if you have an exta 100 buxs for the ZHO.