I would be careful with supplements. Some vitamins can be lethal when given in the wrong dosage.

If you are varying their diet between geckos and chicken I personally would not worry about supplementing their diet. I wouldn't think going several feedings on only chicken would effect them if in fact chicken is deficient in some nutrients (not sure that it is). It would most likely take a long time for vitamin deficiency issues to occur.

Just my 2 cents,

Chris
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Christopher E. Smith
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