First of all, even if your enclosure WAS big enough (more on this later) you will still need to quarantine your new gecko for a bit (up to 3 months) before housing them together. There are no guarantees when bringing new stock into your home. Infections may go either way. This means housing in separate enclosures preferrably in separate rooms. The quarantine enclosure does not have to be huge or ideal, but it should provide the basics.
Your current enclosure is NOT large enough for two adult leos. I would suggest 1.5 square feet for each adult leo. Your current enclosure is just that, 1x1.5 feet equals 1.5 square feed and is most likely a 10 gallon aquarium.
Here is what you could do. Get a larger enclosure: a 20 long or anything that provides that required floor space and security. Set it up and quarentine the new leo in it. Once they are near the same size and you are certain there are no hidden surprises you can then house them together in the larger enclosure.
If you do decide to get a hatchling, you could always move the current leo into the larger enclosure, thoroughly clean the smaller one and put the hatchling in there until it grows to a size that would be compatible with the current one.
Please let me know if anything was not clear enough.
Steven
Royal Gold Reptiles
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