Unless you are using rep-cal(very high d3) and caking the food items with it every feeding, It would be virtually impossible to cause a state of toxicity. Even then it is unlikely. Products like miner-all I and t-rex leopard gecko dust have safe levels that can used every feeding. Around 4000 I.U.'s per kilogram seems to be a safe level for liberal usage. Just a note, when dusting prey, the goal is not to coat them with the product completely. You want to lightly dust them. That being said, I don't dust my leopard geckos food. I just put the mealies in the feeding dish which contains about an 1/8" of the t-rex gutload formula on the bottom. It contains all the same ingredients as the leopard dust, just in different ratios to make it more appetizing to insects. I don't supplement my leos with anything else at it has worked for most of my 2003 beeding season.
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Bill DiFabio
Azteclizard.com
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