Leaf Issues common to all four of my plants

[Onion]

Good day growmies,

• I am growing in Orgasoilux.
• I use dechlorinated tap water.
• Once a week I feed with Environoc Biodyne and Epic 5:2

This is when each of the plants became afflicted with the "rusty" leaf issue:
CK         day 25

LB         day 8

BB2      day 17

WC       day 24

[Weskush]

I've had that in almost every grow. Didn't lead to complications at all. My guess is that it's a micro nutrient issue. I wouldn't stress too much unless it starts affecting the plant in a big way.