Sometimes toxicities take the form of deficiencies in a visual sense.
It hard to know when you are only relying on what the plant looks like to tell you what is going on. too much of one thing locks out another.. not enough of one thing causes an abundance of another... getting in tune with the ladies takes time and experimentation.
And can I mention that different strains can be so incredibly different in forms of diet/environment...
I think you could easily run your ebb/flo at 1.0 EC and see great results, speaking from experience. I will post my veg formula here soon.
Also, I think the biggest problem with ebb flow is the salt ring it leaves at high tide. Can you flush your pots from the top with some warm tap water pH'd at 6.0 in between change outs? I am lucky enough to have a hot water hose and plumbing, but you can still use pitchers of warm water, or a separate res and pump.