Crested geckos are the odd one out among popular pet lizards. They are the one species where insects are not the foundation of the diet, and where a keeper can do everything right without ever buying a feeder. That makes the question people actually ask about them different from the usual one. It is not "which insects do I feed" but "do I need insects at all, and if so, what for". This guide answers both. It is general husbandry, not veterinary advice.
The powdered diet does the heavy lifting
Crested geckos are omnivores that in the wild take fruit, nectar and invertebrates. In captivity the standard modern approach is a nutritionally complete powdered crested gecko diet, mixed with water and offered daily. PetMD's care sheet is direct about it: crested geckos should be given a nutritionally complete powdered food formulated specifically for crested geckos, every day.
That formulation exists because it works, and because it removes the two things keepers most often get wrong with this species: calcium balance and vitamin supplementation. A gecko living on a proper prepared diet is not missing anything.
Insects sit on top of that. They are a supplement, offered once or twice a week, not the base of the diet. Anyone arriving here from keeping a leopard gecko has to invert their instincts.
So why feed insects at all
Three honest reasons, none of them "the powdered diet is not enough".
- Behavior. Crested geckos hunt. A live insect produces a stalk-and-strike sequence that a dish of slurry does not, and that is the clearest enrichment argument there is for this species.
- Appetite. Geckos can go off a prepared diet, particularly when the flavor changes or the mix is made up differently. Live prey is the usual way to restart interest.
- Variety. Whole prey brings a different nutrient profile from a formulated powder, and most keepers prefer not to have any animal on a single food for its entire life.
What insects are not is a way to save money on the powdered diet. Replacing it with insects moves the diet back to something that needs careful dusting to be complete, which is the problem the formulation solved.
Which feeders suit a crested gecko
The constraints are size and softness. Crested geckos are small-headed, they eat at night, and they are climbers, so a feeder that hides in substrate all day is a poor choice.
Crickets
Crickets are the most commonly recommended insect for this species, and the reason is movement. A cricket on the floor of the enclosure at night is the strongest feeding trigger available. Use the smaller sizes, not adults. Uneaten crickets have to be removed rather than left in overnight, because they will chew on a resting gecko.
We do not sell crickets. Dubia roaches are what we sell instead.
Dubia roach nymphs
Small roach nymphs are the practical alternative. They are softer-bodied than an adult cricket, they hold their nutritional value in storage far better, and they are quiet. Because a crested gecko needs only a handful of insects a week, the fact that roaches keep well for a long time in a tub matters more here than it does for a large lizard eating daily.
Black soldier fly larvae
Black soldier fly larvae are the one common feeder widely reported to carry more calcium than phosphorus, which is the reverse of nearly every other feeder insect. They barely move, so they usually need offering in a shallow dish rather than loose. Worth including for variety, not as the main event.
Waxworms and other treats
Waxworms are very fatty and calcium-poor, and geckos take to them enthusiastically. They belong in the rare-treat column, not the weekly one. Most of the worm feeders sit somewhere in that column for this species.
Size is the constraint that matters most
Crested geckos are small, and the standard rule for this species is stated slightly differently from the usual one. PetMD gives it as: no insect bigger than the widest part of the gecko's head.
In practice:
| Situation | What to do |
|---|---|
| Hatchlings and young juveniles | Most keepers do not offer insects at all at this stage, and rely on the prepared diet. If insects are offered, they need to be genuinely tiny. |
| Growing juveniles | Small crickets or small roach nymphs. Move up a size only when the gecko is clearly taking the current size easily. |
| Adults | Published guidance for an adult feeding session is roughly five to ten crickets or three to four worms, once or twice a week. |
| Any age, wrong size | If the gecko is struggling with the insect, the insect is too big. Size names are not a substitute for looking. |
Size grading is not standardized across the trade, so a small from one supplier is not a small from another. For roach nymphs, the dubia roach size chart gives the length in inches behind each size name, which matters more for a small-headed species than for anything else on the site.
Gut loading and dusting still apply
The insects are a small part of the diet, but they are still the part that can go wrong. Two steps:
Gut load the insects before feeding. PetMD's guidance for this species is six to twelve hours ahead. An insect that has been in a bare tub for a week carries very little.
Dust the insects before they go in. Published guidance for crested geckos is a calcium supplement with vitamin D at insect feedings, plus a reptile multivitamin once or twice a week. Because the prepared diet is already supplemented, the total picture depends on how much of each the gecko is actually eating, which makes this a good question for an exotics vet rather than something to standardize from a shop page.
For the comparative figures across feeder species, the nutrition table in our bearded dragon feeder guide puts moisture, protein, fat and calcium-to-phosphorus ratio side by side, with sources.
What to avoid
- Wild-caught insects. Pesticide residue and parasites, and no way to check for either.
- Fireflies. Toxic to lizards, as Cornell University biologists warned in 1999. Never.
- Insects left in the enclosure overnight. Crested geckos sleep during the day and crickets do not.
- Feeder insects as a replacement for the prepared diet. That takes away the calcium balance the formulation was built to provide.
- Baby food or fruit purees containing added sugar or preservatives, if fruit is being offered alongside. Single-ingredient purees only.
Ordering for a species that eats a few insects a week
The practical problem is quantity. A crested gecko eating five to ten insects twice a week gets through a very small number over a month, and live feeders are sold in quantities built for animals that eat daily. Whatever arrives, you are keeping most of it alive for a while.
That argues for picking feeders that store well rather than the ones with the best headline nutrition. Roach nymphs and black soldier fly larvae hold up for weeks in reasonable conditions. Crickets do not, and a tub of dead crickets on day five is not a saving. It also argues for buying small and often rather than large and rarely, and for keeping the feeders properly instead of leaving them in the shipping container.
Of the feeders covered here, we sell dubia roaches, black soldier fly larvae and waxworms, all in the feeders collection. The guide to dubia roach care covers keeping a small order alive between feeds. For the first hour after a box lands, which is where most avoidable losses happen, see what to do when your feeders arrive.
This guide describes feeding a healthy gecko. Weight loss, a gecko refusing all food, or any sign of jaw softening or limb deformity is a veterinary problem, and one to take to an exotics vet early rather than late.