I have used Fox Farm, but you need to use it right. Go to the Fox Farm site and look at the feeding schedule. You will need ALL 3 for vegging: Grow Big, Big Bloom and Tiger Bloom and mix it as directed. THEN use a ppm and a pH meter to adjust to the proper numbers:
When to switch to flowering, then use these: Open Sesame, Beastie Bloom and Cha-Ching:
These all have pH buffers and if you use ro water, you'll find your pH goes really low, like in the low 4's. You'll need to pH it every day or 2. I use General Hydroponics liquid pH up & down....