What midsummer are you growing in ? If it’s coco perlite you want your ph at 5.8 to 6.2.
I’m using BioBizz light. I don’t know about coco perlite but for soil and this nutrient line 6.3-6.5 is where you want to be. Also wouldn’t make sense why only 2 would have weird things going on if the other 2 are also watered at same ph. All these are all same strain.