If one stops eating or if one grows significantly faster than the other (often seen in beardeds that are paired with one more donimant than the other) then i would seperate them. Those are signs of stress that can have ill effects on thier health. A 20g is obvioulsy too small to house them for long too. If you plan to keep them together for ever, you will most likely need at least a 75-90g tank with 2 basking perches at the same height level (in different areas). The most dominant bearded will always be sitting above the less dominant ones. This alone can cause undue stress on your animals. But like i said, if the permenant enclosure is big enough and you have equally sized and positioned perches, you shouldbe ok. Make sure, too, that if you do end up with a male, you seperate them asap.

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1.0 ball python- Azazel
1.0 columbian boa- Brooklyn
1.0 red blood python-Hiss
1.0 peach phase thayeri-Sancho
0.1 creamsicle corn- Pandora
0.1 partial stripe ghost corn- Raven
1.0 Sunglow motley corn-Ernie
1.1 hognose- Pricilla and Odd
0.0.1 smooth green snake- Raziel
0.1 russian tortoise- Manja
1.0 juvie red phase crested- Ichi
0.2 leos- Boji and Kodama
0.1 beardie- Indie
1.0 BTS- Griffon
0.1 Iggy- Sunny
0.0.1 gray tree frog toadlet
4.3 bettas
0.1 pacific parrolet- Mishka
1.1 cats- Cairo and Oberon
2.3 ratties Rizzo, Bree, Blitzkreig, kaos, and Takashi