RQS Royal Gorilla Auto Time Lapse Grow

The plant in the front is showing some sort of stress symptoms. All corners of all leaves are bend upwards. Generally also very interesting to see how different the phenotypes are of the two seeds. I have been feeding as recommended but havent been able to check the EC of the runoff as my meter hasnt arrived yet. So might be to do with the nutrients, maybe light or heat stress. As it is summer right now the temperatures have been quite challenging high