I have no clue as to grafting, but I can tell you that we have a tomatoe plant in the same res as our girl and the tomatoe plant has tripled in size within 7 days and thriving beautifully. We've been discussing moving her because she is absolutely taking over. My point, our tomatoe has thrived with a ph of 5.2-6.2 and ppm of 1330-1350. It seems to tollerate and agree with both the nut requirments and the ph. I can post a pic, if you would like.

Grasshopper playing in the weeds is me!