In regard to the original posters problem, the problem most likely stems from the initial growing medium. As we have already said, when you act too quick trying to fix something that may or may not be what you think the problem is, you can start a chain reaction and cause many more problems. It appears to me to be a fluctuating pH problem, meaning she's not sure what her tummy can digest. If my memory serves me right this is a coco medium, which I have never grown in, which isn't an actual soil. A plant this size needs a full on organic growing medium, she also needs a pH buffer. Having to play with the pH at all unless you are growing hydroponicly should not be a topic of concern for regular soil growing. It seems like we are in a cloud of smoke in regards to what's going on. But I'll bet that this problem was inherently going to occur anyway, given the initial substrate of the growing medium. I don't think blasting 50 gallons of water through is going to be of immense help either, but I suppose anythings worth a shot at this point.
If it continues to get worse, I would have her transplanted into a proper growing medium and then hope I could just brush my shoulders off after applying a fresh medium with the buffer.
I also requested information on your metal levels of your nutrients, this information was never provided to me.
Hopefully we can get her back on track, I also don't understand why you are bringing her inside under the lights anymore, I would say just let her grow, putting her from the fresh outdoors and into that little grow shed for the measly lighting probably does more harm than good, you would be surprised how much work these things are doing on a cellular level in darkness. Fresh air is important, I also hope she is of stable genetics, flashing her with Sunlight and then artificial light is definitely not an ideal situation, you want her adapted to her home, she needs to make peace with the Earth and mother nature. All of this crazy intervention and speculation is not making her feel good. Sometimes less is more.