If you must get two then get two females, which i belive is 0.2.0. Although im not sure how you are going to sex them as babies.
But as most people on here would say BD's are solitary animals. They dont really want company. If you get two males they will most likely fight, male/female will constantly try to make babies and its stressful on the female. The only real hope you wouldd have is two females and they need to be around the same size. Thats usually how it happens. My two F/M want to make babies all day long. At least the male does, female is iffy sometimes and i think she gets stressed when I let them out at the same time sometimes.
As for a tank, minimum size for *one* BD is a 40gallon breader. If your using two go with at the very least a 75 gallon. Floor space is more crucial then height. If your going to get two i would buy two seperate 40 gallong tanks.
But remeber, they are quite happy alone.
-----
2.0 Ball Pythons (Kurt the Snake ~ Frosty McFry)
0.1 Leucistic Texas Rat (OogieBoogie)
0.1 Kenyan Sand Boa (NoFingers McGee)
1.1 Bearded Dragons (Saku ~ GracieJ)
0.0.1 Albino Ornate Pacman Frog (Jabba the Frog)
0.0.1 Ornate Pacman Frog (Hooter)
0.0.1 Emperor Scorpion (Cecil Peoples)
0.0.1 Usambara Tarantula - (FBD - Fire Ball of Death)
2.0 House Cats (Bill ~ Ted)
And a partrige in a pear tree...
~!Bearded Dragon Custom Cage Design!~