hi,
i know that 1.3 leos do alright in a 20gal long, i'm not sure how many more gallons after that. i only have 1 leo & don't plan 2 breed, so i don't know the tank size answer and the babies answer.
but, i do know that leopard geckos can do fine on a mealworm diet. you can toss in supers, crix, and silk worms if u want to add variety. if you want to feed a wax worm (as a treat), give ONE every week / every other week to prevent addiction & refusal of other foods. but mealworms make a great staple diet. (pls remember 2 gutload / dust!)
similar to beardies, males shouldn't be housed together.
good luck & i hope u get more answers soon! take care 
[aimEe]
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0.1.0 Albino Leopard Gecko (Marlene)
0.0.2 Fire Bellied Toads (Norman & Forman)
0.2.0 African Dwarf Frogs (Hobo & Bobo)
1.0.0 Fighting Fish (Blue Balls)
0.0.2 Hermit Crabs (Kirby & Furby)
1.0.0 Black Lab / Pit Bull (Mikey)
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