Sounds like your on track I run 70 to 72
start of flower the gradually bring it down during Mid to late flower.
I keep my root zone at about 69.
Any thing colder and it slows the growth
I go per tray depending on the strain.
every 4x4 I’m pulling Anywhere from 1 to 1.9
Scrog. 4 per tray
sog per 4x4 I get 1. 2 to 2.6
Per 4x4 tray thats usually 8-10 plants.
I like to see what they respond best to.
Next go all Sog. 10 plant per