They need enough room to move comfortably, and to have enough hides for your group. Mine are in rack systems, though I would prefer 30 gallon tanks. I use caging that is about 24"x 18". 3 leos per cage. They use it all, but I never see them trying to get out. I take them out often for extra exercise too.
As far as breeding size and weight there are many versions to this theory! I go by the health of each individual, not the weight. Most of mine have been between 10 months and 18 months. Their weight I do not know. If they eat regularly and have fat tails then go for it. For a good book get the gecko manual.
For an incubator I would go with either a 10 gallon fish tank with a piece of styrofoam for a lid or a fish shipping box that your local petstore will probably be glad to give you. I heat mine using room temps in a temp controlled room. But originally I used a large pickle jar with a submersible heater.
And yes, you can kill the embryo by rotating the egg. It's always best to mark the top of the eggs after they are laid to always be sure right side is up
Julie.
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