4 froglets in regular 20 gallon (not long). How long before upgrade of tank?

[Lejin2]

Hello! I have four new tiny clawed froglets that are about 2.5-3 inches long. I have them in a 20 gallon aquarium. Hopefully I can get away with not upgrading to something larger for a while? What's the growth cycle for these guys?

[jbigtoe]

I am not an expert about this, but they should be fine for the first year or more I think. Is the 2.5 - 3 inches including their arms and legs? I have a 20 gallom long that houses one right now, but but will have three more in the next few months depending on growth rate.