Welcome aboard Tuf.

This is just a guess brah.
So wait for someone who actually knows what they are on about before taking action, yah?
But, it looks like a Phosphorus lockout.
Is the main stem as red as the petioles?
What are you using to adjust PH?

We expect some yellowing of the fan leaf at 30 days, but those spots are not what I'm used to seeing.

There's a symptom chart in the archives here.
I'll go rat about and see if I can find it for ya.
BRB

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Weezard
Weezard Reviewed by Weezard on . Yellow leaves with spots 297190297191297192 Hydro Growers: 1. Are you growing from seed or clones? clone 2. How old are your plants? day 30 flower Rating: 5