plant diagnosis

Hey guys- On my second grow and having an issue with one of my auto strains: RQS- gorilla auto. She started with a couple brown spots on just a couple of the leafs but has now started to take over (see pics attached). Could really use some expertise on diagnosing as I have been spinning trying...

The first plant is what I’m worried about. Lemme know:) Week 1 with devils cream auto under 600 watt veg bulb in a 4x4x6 tent with fans and all that good stuff 3 out of the four are doing well from what I can tell, I’m using fox farm of soil, there trio later on, as well as cal mag and bud...

Im hoping somebody has seen this before and can offer some advice. I started 2 Blackstone seeds, one came normal but the other lagged behind and when it popped it appeared to have the seed hull still attached to the stalk but has since opened completely and is now exposing the first green...