Brown Spots on leafs that are cracking!!!HELP

Heres the details:
Im using foxfarm ocean forest. No nutes yet. Watering with ph'd water every 3-4 days. The runoff is usually between 6.2-6.6.

A few of my fan leafs are starting to do this. I'm not sure what it is, it doesn't seem to be spreading in anyway.
Anyone have any ideas, its making me really paranoid aha.

inside or outside. doesn't look serious. if it gets worse then i would worry. the soil has a lil bit of nutes but not enough to do any burning.. might just be a fluke..

Thanks man. Theyre in a tent indoors. Temps 75-80 during the day about 68 at night.