I culture both. The smaller ones for the new-born chams, and then the larger ones once they reach a couple weeks old. They'll eat both sizes from hatching, I just prefer to start with the smaller ones. The smaller ones also breed faster. I got my original cultures from canadianfeeders.com (I live in Canada). They arrived swarming with flies and maggots. For mine, fruit Flies remain a staple food up until the third month, when I start tappering down (but still offer them right until they stop accepting them, which is not until at least month 6). I use three different types of culture medium, hoping that this varies the nutritional value the flies offer my babies.

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SandraChameleon@gmail.com
BC Canada