my concern with this is that if you are feeding the crested gecko diet MRP, adding more vitamins and minerals would not necessarily be a good thing. how reputable is your vet? i took some reptiles in to a local exotics vet once who knew absolutely jack $#!^ about cresteds, and told me not to feed the MRP, but to feed baby food, that they needed UVB light, and that if i fed phoenix worms, be sure to gutload and dust them. she was full of crap. so just be wary of where your advice comes from.
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4.1 snakes, 4.6.1 crested geckos, 0.1 gargoyle gecko, 0.0.2 red-eyed tree frogs, 2.0 devon rex cats, 1.0 betta, 0.1 sun conure, 1.0 lovebird