I don't know if anyone uses a different vitamin dust for pygmies or not. I do not have pygmies, but have used Herptivite with beta carotene for years. I only use it about once a month and gutload my feeders carefully. But I know that the variety of small feeders available for small chams is more limited. Hope this helps.
i've been using rep-cal w/ D3 and herptivite with my pygmy, same stuff i use for my dart frogs. they seem to be thriving on the mix and rep-cal isn't loaded with phosphates. I dust with the herptvite every feeding, and mix in the calcium about twice a week. mind you i've only had my pygmys for 4 months, but they seem to be doing great. I have two females and one male, and i think they may have laid a few batches of eggs, but i haven't dug them up and haven't seen any babies yet, but crossing my fingers.