If you've just brought a crested gecko home, he might be very stressed out. This can cause him to stop eating for a while because he's not used to his new environment.
Providing him with lots of hiding spots can help him feel more secure and encourage him to eat. Keeping his tank and enclosure a decent size will also ensure that he can move around freely without feeling cramped or anxious.
Misting the tank regularly is another essential part of caring for your gecko. This helps to maintain a healthy humidity level in the tank which will encourage your gecko to drink.
Feeding a diet complete with fruits, vegetables and invertebrates is recommended for geckos as it will provide them with all of the nutrients they need. Be sure to check the ingredients of the food you feed your pet to make sure it's free from preservatives and other additives that can be harmful for your gecko.
Crested geckos are omnivores and eat a wide variety of different foods from insects to fruits and vegetables. They don't need to be fed every day like mammals do, but they should still be offered fresh food at least once a week.
If your gecko stops eating after 2 weeks or so, it may be time to consult the vet for advice. This is because this type of dietary deficiency can lead to anemia, which is serious for geckos. The vet can advise you on the best way to reintroduce food and monitor your gecko's weight for any changes.