Is this nute burn? humidity problem? or heat issue?

Ok, this is an old post but I think I know what was happening. It was either root lock, or too much grow big formula. I read that too many nutrients put salt into the soil which locks out calcium/magnesium. Pretty interesting.

After putting them in big giant Wal-Mart reusable bags and capping each with more fox farms ocean floor dirt, the problem seems to be resolved.