I know how Pharaoh must have felt. I got hit with a plague on all three girls. Don't know if it is the soil, I never doubted your reference to poop DAB, or maybe they don't like the 1/2 tabs, every tip burned including new growth. Lockout for sure as they showed many deficiency symptoms. Copper, Cal, Mag, and Phos primarily.
All ph has been in the 6.3- 6.8 range. No extra nutes added but supplemented with 1/8 tsp super thrive, 1/2 dose of rhiz and emergency dose of cal/mag per gallon.. Foliar fed with 1/2 diluted of that.
Started at 40 cm from light and moved up to 48 inches at first sign of trouble, they like it there. So I went into emergency flush mode of 2 gals 6.8ph flush. They are making a comeback but will be stunted as hell.