I'm with the guy that suggested Aphids. I had 2 die and 2 more badly damaged this year. did not touch 7 others. @ just drooped and died. They came in from my tomato's that were just on the other side of my fence from the pot.
But as for nutrients, I have found a 2 part nutrient that delivers everything a pot plant needs. KISS is my motto. Keep it simple stupid. lol no cal mag no ph up or down nothing but it. the plants are never any color but green. My head was dizzy reading everything you put in. lol
Low temps won't cause that. pH is a possibility. How wet is your soil? Did you let your dry ferts compost before planting? Perhaps the addition of bottled salts (age old isn't organic) slowed the decomposition process and the increase in moisture might have triggered the soil to heat up with uncomposted dry ferts. It looks like hot soil burn to me, but don't quote me on that.
No, don't use anything with more carbonates in it. Dolomite lime (CaMgCO3), oyster shell flour (CaCO3), and the like are to be avoided here. The issue @Bulldog420 is discussing is caused by carbonates and bicarbonates. If you dump dolomite lime (CaMgCO3) then you're loading up with even more carbonates. The molecule you need to watch out for is expressed as CO3 (can't recall the expression for a bicarbonate).
Edit: I see @Slownickel@Blaze@Bulldog420 gotcha covered. Listen to these guys. Seriously. If they correct me, listen to them, not me.
Guaranteed his conductivity is high. Hopefully we can make his analysis a case study so that all can see how important it is to understand where you are and where you want to go....