Regardless of if your adult could or would eat the juvie, I would not put them together until they're about the same size. Smaller geckos get stressed out because of bullying by the larger ones...this is usually due to competition for food, territory, etc. This may not kill the smaller one, but it will most likely slow its growth and delay any future breeding plans you have.
Putting them on the floor is only going to freak both of them out and they're both going to try to run and find somewhere to hide. That's not going to help you determine how they'll act when they're sharing a cage and trying to eat the same food, etc.
If I were you, I'd keep the 3 month old in a completely separate cage to make things easier on yourself, not to mention having at least somewhat of a quarantine period. You don't have to spend much money either. A $5 Critter Keeper or Rubbermaid is all you need.
>>I have a 29G partitioned about 20/80. I have a 3 month old in the 20% partition, and I just ordered an adult female to put in the 80%. I eventually plan to breed them, and will get my third adult once I can determine the sex of the juvie. My question is how old should the juvie be before I remove the partition and have them share the whole 29G? I have read that adults may see hatchlings as food, but what about 3 month olds? Would this put any extreme stress on the juvie? If 3 months is too young, then when would be a good time to introduce them? Should I try putting them together outside their enclosures, like on a table or the floor or something and see how they react? What does everyone think?
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>>-Bill
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>>1.0.0 Albino California Kingsnake
>>0.1.0 Colombian Red Tail Boa
>>0.1.0 Leucistic Patternless Leopard Gecko
>>0.0.1 Red Flame Crested Gecko
>>0.0.1 Argentine Black and White Tegu
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>>My Home Page
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>>BoidsNTegus@insightbb.com
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Anthony Caponetto
www.ACreptiles.com