my first grow OG KUSH LEAVES CANOEING !!!! WTF?

In my shed I have 4/6 table with 20 geo pot holding the clones. 1000 watt hid digital ballast. Lamp hood is vented with squirrel style fan. Run oscillating fan and portable dehumidifier 24/7 humid set at 50% 18hour light cycle. Am I missing anything? also
yesterday I noticed some of the plants the top leafs are canoeing. Weird not all plants affected but once that are its mainly top few leafs. Any thoughts been bugging me last two days, can't wait till tomorow for the hydro shop to open so I can buy a pH tester>!

I am having the exact same problem with OG Kush. Can anyone help??

Maybe a nutrient burn or too hot. Put your hand by the leaves that are camping and feel the intensity

I call it Growing pains. The center of the leaf grows to fast for the sides to keep up. I too was thinking what am I lacking or bad happning? when just give it time to mature. If you know everthing is good? it can be too good! LOL

Check your temps, and pH