Gecko Food

Can a crested gecko last 3 weeks with baby food fair.

No, if the food is not changed every day. The light is going to dry in a day or two and it will not be good. And it's healthier for baby food sprinkled dust calcium as geckos have very small bones and need extra calcium. Crickets are healthier, they can also be dusted, but you do not want to put a lot of them in the cage at one time or they could gang up and actually try to eat the gecko.