The young one is way too young, and the older ones are way too skinny. Breeding takes a lot out of females and makes them lose weight, so they need to be fat before you breed them, preferably 45-65 grams or more. They should also have reached their adult size, you shouldn't breed a gecko that is in the middle of growing up, you could stunt uits growth. They also need to be healthy. Have you had a fecal done on your skinny females? Usually when geckos are skinny it is because they have some kind of infection or parasites. It could be something as easy to treat as worms.
Generally the rule of thumb for breeding is over one year and 45 grams, however if you have a fat gecko who is large for their age, say 55-60 grams or more, you can try to breed earlier than one year, like at 8-10 months.
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Sarah Stettler aka Starling
Sarah@stargecko.com
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