Is this a deficiency of some kind ?

Hello, i have this various strains under 600 MH light. Biobizz light mix substrate. I fed twice already with canna terra vega, cannazym and nitrogen boost n27%. The pH of the feeding solution is 6.0-6.2 it's been a week now since i've noticed this yellow spots on the leafs. Is this a deficiency of some sort ? any help is apreciated.

Flush with water at 6.5 then make the feeds 6.5 .

Thanks Buds, u always give precious help dude. Appreciate that. I'll feed with 6.5 pH solution and i'll also buy some microelements fertilizer to exclude that possibility. nice avatar btw