Many thanks for all the comments so far. I was whooped and crashed out early last night.
I am growing in new soil, using the Greenfields mixture I got at Worms Way. I have been using Slacker with great success but Worms Way said they no longer carry it in their stores and are selling their stock from the warehouse. I liked the Slacker in that it seemed to dry out quickly so one good watering per week was find. With the Greenfields it seems to hold the water much longer and I can go a good 10 days or so before it seems it needs watering.
As for nutes, I am using the Fox Farm Trio but still seeing slight deficiency in the leaves so I thought perhaps adding CalMag with every other feeding I could avoid deficiency. I opened a new container and when trying to pour into my little measure spoon it spilled out, prolly a couple tablespoons worth. I thought I should dump it but at the time the water was the only “seasoned” water that I had on hand in that it was tap water that had set out for a few days to allow the chlorine, etc to dissipate so I went ahead and used the water.
After the 2nd day many leaves had turned very dry and greyish green, there is still some active green life but most of the big fan leaves have gone bad
I have been flushing the soil with tap water and the PH drops by 1.5 from the bucket to runoff. our local tap water comes out at 8 and my runoff is 6.5 of course regular watering I nute and PH to 5.8 or so and use that but just for the flush I am using tap water.
its looking pretty bad according to the pix but I will keep flushing the 3 gal Smartpot all day and then remove all the dead growth and put it back under the 18hr T5 light.
Anything else I can do? I certainly learned a lesson here that wont be repeated. If I lose the plant it wont devastate me but it would be nice to save this Goldleaf and Jack Herrer.