The size is big enough for two adult dragons but there are many issues that arrise when you house multiple beardies together.
The first are foremost being that one beardie is always dominant and the less dominant one gives up the best basking spots and acess to food and also lives in a state of constant stress. This leads to failure to thrive and grow properly, parasites and if left that way ultimately death. Dominance in beardies is not always as apparent as aggression and biting. It can be very subtle...the basic comparison is how would you feel if you were in school and the school bully suddenly came and sat down next to you at lunch. Even if he didn't do anything...you would probably lose your appetite, right? And if this happened day after day after day.... You get the idea. This effects them mostly, but not solely, when they are younger and growing at a rapid rate.
Another big problem is that with baby beardies you cannot tell their sex at a young age. If they are housed together from the time they are babies and they turn out to be two males you will come home one day to find them fighting. Then they will need to be seperated and have any wounds treated, and if they are left unattended for too long, one of them might be killed. If they are a male and a female then they can breed when they are too young and the female can become eggbound or have a myriad of other health problems. Young beardies need to have all their effort going towards growing, not towards developing babies.
Even if they are adult beardies, one male and one female is a bad combination. The female may be overwhelmed with the males breeding efforts and can spend too much time gravid and not enough time recovering, thereby affecting her health. The best way to house multiple dragons is in a breeding group of one male to two or three females. But if you do this you need to be well aware of the specific health and husbandry issues that apply to breeding colonies and you must also be prepared to deal with many many babies, or at least gravid females (wether you decide to incubate the eggs or not is up to you)
A few other secondary issues are that diseases can be passed easily from lizard to lizard. If one lizard becomes sick it is very likely the other will as well and then they will need to both be treated. It can also be difficult to notice when one of them is sick. You may not notice if one isn't eating as much because the veggies keep disapearing and you cant tell which dragon it is. You may also find suspicious looking stools or vomit and wont know which dragon they came from unless you catch them in the act.
The bottom line is that its not a good idea, especially with babies. I would advise raising the babies seperatly to ensure good growth until they are sexable. Once they are over one or two years of age if they turn out to be both females you can try housing them together. As I said before, any other combination of sexes is not a good idea. Colonies can be tricky to deal with and are probably best left to the experts or those interested in breeding many babies. If you scroll down and read some of the more recent threads there are at least 3 or 4 threads addressing this issue...all with the same conclusion...do not house beardies together. The thread entitles "One larger and one smaller" is a good one to read.
If your babies are already housed together i would seperate them, at the very least until they are adults. This will give them each a fair chance to grow and thrive to their full potential.
As far as nutrition, check out www.beautifuldragons.com, they have an excellent nutrition page, as well as tons of really up to date information on care that will help bring you up to date.
Good luck with your babies!
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0.1 Bearded dragon
0.1 mexican Black kingsnake
1.1 Leopard Gecko's
0.0.1 Tokay Gecko
1.0 Blue Tongue Skink
0.0.1 Reverse Okeetee Corn
0.1 Anerythristic Corn
0.0.1 Red Tegu
0.1 Bullmastiff
4.1 Cats
