I am guessing that, as is the case with Terrapene species, there is not really an *exact* size at which they reliably breed: the best information to look for would be size at maturity.

Here is an online article that may be helpful to you (see link below). I really don't know much about Cuora or now Cistoclemmys species and there just aren't many people posting on here who keep them. My understanding is that they are somewhat more aquatic than Terrapene species.

I would suggest that you join the online yahoo group for the World Chelonian Trust (http://chelonia.org/) for husbandry pointers for this more exotic species.

I hope this helps. Enjoy your new turtles!
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