how many geckos, or insect feeders of any kind, do you have? it's not worth the trouble for just a few. basically you need to start out with about 1000 crickets, which can barely live in a 20 gallon long. and then as babies grow you need to keep sorting by size. mealworms, are maybe a bit easier. if you buy 1000 mealworms and keep them on a bran cereal bedding, with a carrot for moisture, they will probably breed on their own. i know that when i buy lots at a time, i often find babies just popping up.
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your head will collapse, but there's nothing in it, and you'll ask yourself, "where is my mind"
if you have AIM, IM me at iluvblackfrancis