10 gallon minimum for ever pair (male&female)
add +5Gallons for every additional pygmy to the colony.
every male should have about 10-15 gallons to himself.
Tanks are ok but i suggest using terrariums with vertical height. I use to have one 29Gallon tank that I housed one of my colonies. It was a 1.5 colony and they were fine. All m other colonies were in exo-terra/zoo med terrariums. Now I have them all in these vertical terrariums. A 1.2 colony will do great in a 12x12x18. Or 1.3-1.5 will do great in a 18x18x24. People say they don't need the height but a Pygmy will climb if given the chance. And I always offer my chams what I can. Plus, it's easier to keep the temps in the right range bc of the vents, easier to clean without towering over your chams and stressing them, and easier to view if you set-up the terrarium correctly.
glass aquarium is fine, but be sure the top is screened and you can safely use a light above it. Communities are fine. In small enclosures only 1 male and up to 4 females. Be sure to give plants live or fake and a dirt, sand, or coconut fiber bottom for the girls to dig and lay eggs in.