Housing
Leopard Geckos are among the largest geckos with adults attaining a length of around 8 or 9 inches. Most leopard geckos have a yellow background with brown spots covering the adults. Juvenile geckos have a predominantly striped pattern that fades to the spotted pattern with age. They differ from many geckos in that they have eyelids and lack adhesive lamellae, meaning they can't walk up vertical services.
Males are usually more heavy-bodied than females, with broader heads and thicker necks. The best way to sex them is to look near the underside of the tail base. Males have a V-shaped row of pre-anal pores which exude a waxy substance. Hemipenal bulges can be seen at the base of the tail of sexually mature males. Females have pre-anal "pits" - pores which are not filled nor exuding the waxy plugs. Juveniles can be sexed as early as one month of age with some degree of reliability if you use a 10X magnifying glass.
HOUSING
One baby leopard gecko can be kept in a 10-gallon aquarium; adults can be housed in a 15-gallon+ long aquarium with a tight fitting screen lid. Floor space is more important than height because leopard geckos can't climb on glass like other geckos. To prevent territorial fighting, males should NOT be housed with other males.
Newspaper and paper towels can be used on the bottom of the enclosure. Sand can be used with adults, but never juveniles! There should be several hiding places throughout the cage as leopard geckos are nocturnal and hide during the day: one of those hiding places should be kept moist (keep slightly dampened sphagnum peat moss in it) to help the gecko shed properly. Provide a shallow water dish that your gecko can easily drink out of. Change the water daily.
If you are using newspaper or paper towels as a substrate, you will need to change them whenever you see that they have been soiled. Sand will need to be replaced approx. 3 times per year. When cleaning the enclosure, soak the entire tank and furniture in a 10% bleach or ammonia solution. Rinse well with hot water. Dry thoroughly.
TEMPERATURES
The cage should have a cool end, at about 80 F, and a warm end, at 85-90 F, allowing the gecko its regulate its own body temperature. The optimum air temperature by day is 86 F and 78 F by night. To achieve these temperatures, you can use an undertank heater and incandescent reptile lamps. Hot rocks can cause thermal burns or electrical fires, so they should NEVER be used with leopard geckos.
DIET
Leopard geckos will thrive on a diet of crickets, mealworms, and, for adults, an occasional pinky mouse. Babies and juveniles should be fed every day until full (4-15 insects appropriately sized). Adults should be fed 6 to 10 insects every other day. Crickets should be dusted every feeding with a calcium and D3 supplement like RepCal Calcium and D3 or SFT Miner-All "I". Place the insects in a plastic bag, add a pinch of calcium and shake to coat the insects with the powder. It is also a good idea to remove crickets after a half hour to prevent them from harassing your gecko.
NOTES:
Leopard geckos should not be handled during the day or by the tail.
When you get your gecko home, call an experienced reptile veterinarian to schedule a fecal check (and an appointment). Physically your gecko may look fine, but reptiles do not usually show signs of real illness until it is too late.
RECOMMENDED READING
The Leopard Gecko Manual by Philippe De Vosjoli
LEOPARD GECKOS: Past & Future http://www.leopardgecko.com/emcare.html