The olders leaves started to die and to turn this yellow-brown color.
I thought it could be the temperature (I am about to receive my temperature hydrometer to measure that), or over/less watering, or nutrients.
The plant looked great a week before.
The wrinkle on the leaves and the browning leads me to think ya are on the right track with a heat issue. I'll assume there is a RH issue also that needs to be corrected. Try for around 70% at this stage. 🤘😤
Hello!
Burnt leaves can also indicate too many nutrients.
Did your soil mix that you bought already contain fertilizers?
Then your plant can usually continue with this until week 6.
Definitely check this out!
Otherwise, I would also consider a heat issue.
Good luck! 👊