Yellowing Leaves, Striping, leaf loss

[Waira]

:smoking: Hi SJ,... well, I'm kinda stumped here,.. Biobizz shouldn't do this so easily, usually it's the opposite problem, not enough nutes,.. that line is so mild,... they look overall starved, but have burnt tips,... pH is OK, or not out enough to cause lockouts,... (is you meter calibrated and stored in the right solution?)... it is a bit odd that you're getting a slight rise in run-off pH,... look at the soil components on the bag; is there any lime/dolomite listed? it's possible the soil isn't mixed well,... even nutes can go bad especially organics!
Amamzon will have the A8 (Control Wizard) or an equivalent in EU, under a different brand name,... identical units though, all from the same Chinese factory! ...look into getting a basic TDS/EC meter too,... not expensive at all, and you can test your water, nutes and run-off which can provide vital clues at times,...