stick with the pure CGD unless you want to try the 2-part nectar system.

just check for fresh fecal matter, and make sure they're not rapidly losing weight or looking skinny. what are their temperature and humidity ranges? sometimes geckos just eat a little, and sometimes they go through growth spurts where they eat a ton.
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4.1 snakes, 4.6.1 crested geckos, 0.1.1 gargoyle geckos, 0.0.2 red-eyed tree frogs, 2.0 devon rex cats, 1.0 betta, 0.1 sun conure, 1.0 peachfaced lovebird, 2.0 lineolated parakeets