Not sure what’s suddenly going on with these leafs they like aren’t growing complete
Almost looks to be light maybe? Lights only at about 30-35 % and suggested more at this point in growth using Mars hydro fc-e 6500
Looks like some mechanical damage to leaves. Did you try topping this?
Definitely looks like some nitrogen deficiency…
From looking at bottom leaves…
What kind of soil type?
Might not be enough nutrients in your soil…
More info will help
Happy Growing
Side view? Ppfd?
Check the pH first.