From what I understand its very had to overdose a dragon on these calcium products. It is however, necessary to dust your crickets. The amount of times you dust per week depends on the size. There is a chart on beautifuldragons.com that tells hwo manytimes/size ratio.
Also if you didn't know you can get a "cricket shaker" at PetsMArt that holds the crickets in the top and powder in the bottom. You turn it over and the powder goes to the top and coats the crix then the remaining powder falls to the bottom for the next usage.
Later,
Robert
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A foolish consistency is the hobgoblin of little minds,
adored by little statesmen, philosophers and divines.
Ralph Emerson