I have three maritime babies in one ten gallon, and 2 easterns in another, and they have a lot of space. Making the tank bigger would only stress them out if they are hatchlings, they'll grow really well in the 10 gallon for now.
I keep my hatchlings in small groups in 27 Liter tank and they stay calm.
As I´ve tried before to raise them in a normal enclosure, they´d become nervous and shy. They had place enough to fix a flight distance and did it.
That would be a rather large tank for just some hatchlings. It wouldn't really affect their growth any....they'd grow just as fast or as big in a more appropriate sized cage. I do like giving my snakes big cages to "roam" around in, but they shouldn't be so big that you have problems keeping track of the snakes or the snakes have problems finding food, water and the right temp. conditions. A single 10gal. for say the first 6 months to a year or so would be just fine for them and wouldn't adversely affect their growth. Things are always a bit different with hatchlings, but a rule of thumb I like to use is that the cage should be as long as the longest snake. For more then one snake in a cage, I like to use 125 square inches per 12in. of snake to give them enough room. Hope this helps.