Hello, I'm new here

I have wanted to keep a tree frog or two for some time now, and I just found a little gray tree frog (green colored and small, so probably a juvenile?) outside that I'm thinking about keeping. I have a 10 gallon tank with a wire mesh lid that I can house him in. If I wanted to collect more frogs though, how many could I keep in this size tank? And can I keep just one, or do they enjoy company?

I've also been looking at the small terrarium by Zoo Med with dimensions of 12"x12"x12". Would this be large enough for gray tree frogs, and if so, how many could comfortably live in there?

Thanks in advance for the help, and I'm sure I'll be posting more questions as I go. I have already read through the gray tree frog care sheet and found it very helpful!
http://www.frogforum.net/frog-toad-c...heet-Info.html