It's not temperature. Soil or watering practices is my guess. What's your water like and what are you adding? I'd cut out the Recharge for now too. That's not a great sign that there's no label on the bag of soil. Soil is my main thought.
Another bad sign. Their website doesn't work. Sounds...
There's another new one that just joined too, but bk already called him out.
Edit: Maybe bk figured out it's one of his clan members. I see he's following him now, :lol::lol::lol::lol:
FFHF is fine from the start without adding anything. I'd get a couple dry organic nutrient mixes to top dress. EWC is always good to grab too. And extra perlite of you want.
He can't help it. He was born that way. :bigjoint: