Mealies are fine as a staple diet. I have kept my leos almost exclusively on superworms (I have had my geckos for 13 years)and they are doing great. I like superworms because it takes less to fill up your gecko, they move around a lot, and they are easy to keep. I keep mine in a small Kritter Keeper with oats, bran, dry baby cereal, and baby carrots. My leos eat 4-5 worms per feeding, 3 times a week. So that is 12-15 superworms a week per gecko. I also feed my leos in a separate container and that keeps the cage clean from uneaten or dropped food. I never feed crickets (they are noisy, messy, and smelly) but I do supplement my geckos with f/t pinky mice, butterworms, and meal worms a few times a month.
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0.1 Hogg Island Boa
0.0.2 Corn Snakes
0.3 Leopard Geckos (my very first reptiles-I've had them a LOOOOOOOOONG time!)
2.0 Wonderful Dogs