Fabric pots come in as small as 1 gallon( which are hilariously rinky dink) but 3 gallon seems to be ideal till gender identity, def would suggest it.
What’s the brand on the soil mix? Some premix soils def need the additional perlite, from what I’m seeing what ur using is one of em
Soil mix is easy, I’ve got a thread on it u can find by searching " let’s make 500 gallons"
Basic recipe is:
50% compost ( I use half and half mushroom compost and Scotts humus and manure)
25% coir or peat moss
25% perlite, pumice, lava rock, or rice hulls
1 cup per 10 gallon of Dr earth veggie herb and tomato
I grow here in az in the hottest and dryest part of the country, today was 105 and humidity is 0-5% here. Never needed a humidifier and would highly suggest cutting that part out for now till ur plants aren’t getting choked out by all the moisture, also ur temps should be a lil warmer pushing closer in the 80’s, should speed up growth better too