Interveinal chlorosis on older and new leaves. Magnesium deficiency?

Thanks for the replies! My pH meter is calibrated well and I don't let my nutrient mix to sit for long. Ive been supplementing 0.5ml/L of Biobizz cal mag as I'm using filtered water. But looks like I gotta raise it up higher and perhaps increase the pH to 6.5 to help with the mag absorption.

If it’s soil, I’d be worried that my PH pen or device might be off a bit.. Cuz once it dips below 6.0 the magnesium uptake gets low on soil. I’d be tempted to run closer to 6.5-6.8 and maybe add some Epsom salts to the feed. I use a pinch per liter or so.. upping calmag may work as well but I’d look for a pure source of mag. Good luck amigo!

Are you letting your feed sit for 24hr before adding into the reservoir? Been told by a few growers that BioBizz tends to drift downwards in PH before it settles. And its best to premix it all and wait 24hrs before using it and do a final PH adjustment. as for soil grows, I keep my PH at 6.5-6.8 Best Of Luck