Sandfish skinks are insectivores, which means that they depend on a diet of bugs for optimal health and nutrition. Their bodies are uniquely evolved to be able to detect and pinpoint the movement of insects up to 6 inches (15cm) away!
How much do sandfish skinks need to eat?
It’s difficult to say exactly how many bugs to feed a sandfish per day, as this depends on the type of bug, the age of the sandfish, and the size of the bugs in question.
- Hatchlings (under 3” long) — 2x/day
- Juveniles (3-5” long) — 1x/day
- Adults (at least 5” long) — Once every other day
Offer as many bugs as the sandfish will finish in about 5 minutes. However it’s alright to leave some loose in the enclosure, as this will give the sandfish something to chase throughout the day.
What do sandfish skinks eat?
Sandfish rely on vibrations in the sand in order to find prey rather than using their sense of smell, so they need live insects, not dead ones.
- Small grasshoppers/locusts
- Dubia roaches
- Discoid roaches
- Red runner roaches
- Black soldier fly larvae
- Darkling beetles
The feeders you offer should be no larger than the widest part of your sandfish’s head, because although they do chew their food, they still swallow the bugs that they catch more or less whole. Offering feeder insects that are too big may result in refusal or possibly choking.
You may notice your sandfish occasionally plunging its snout or even its entire head into the sand — this isn’t a failed attempt at hiding; it’s actually how they detect the vibrations produced by insects hidden under the sand. (Use of vibratory cues for detection of insect prey by the sandswimming lizard Scincus scincus by Thomas E. Hetherington)
For information about the nutritional value of different insect feeders, read our article, Feeder Insect Nutrition Facts for Reptile Keepers.
Can sandfish eat fruits and vegetables?
As an occasional treat, yes. Based on findings in The comparative diet of three Saharan sand dune skinks by Omar Attum et al., it is speculated that wild sandfish may snack on vegetation when they can’t find bugs to eat. However, like an average human presented with the choice between steak and salad, they prefer the bugs.
Here are some safe options to try:
- Millet seeds
A small, shallow bowl of reconstituted crested gecko diet powder (Pangea or Repashy brand) may also be accepted.
All fruits and vegetables should be chopped into very small pieces to be easily eaten. And let me emphasize again: fruits and vegetables should be used as a treat only. Attempting to feed a sandfish solely on an herbivorous or vegetarian diet will
result in the animal’s death.
Should I feed inside the enclosure?
Some new owners may be concerned about feeding their sandfish inside a tank full of sand. After all, won’t the sandfish ingest the sand when it catches its prey? Yes, but there’s no cause for concern. Sandfish’s stomachs and intestines are built to handle sand ingestion — and in large amounts at that. In Adaptation to life in aeolian sand: how the sandfish lizard, Scincus scincus, prevents sand particles from entering its lungs by Anna Stadler et al., researchers found that 40-60% of wild sandfish poo is, in fact, sand! They pass it just fine as long as they are adequately hydrated and have high enough basking temperatures.
Plus, letting feeder insects free roam in the enclosure for the skink to find will keep it well entertained, as it will spend all day chasing them. This is good enrichment as well as a good way to encourage exercise.
Dietary supplements for sandfish skinks
Calcium is essential to a captive insectivore’s diet because captive-bred insects have a chronically low calcium-to-phosphorus ratio. When there is more phosphorus than calcium present in a food, the animal’s body has to source calcium from its own reserves to properly process the phosphorus. Dusting feeder insects and invertebrates with calcium helps correct this imbalance.
For this reason, ReptiFiles recommends lightly covering all invertebrate prey with a high-quality reptile calcium powder supplement (excepting isopods and hornworms, which are naturally high in calcium). Here is a list of ReptiFiles’ preferred calcium supplements:
To “dust” prey in calcium powder, put the prey in a plastic bag with a little bit of calcium powder, seal, and gently shake until lightly coated.
Calcium dusting is not necessary for whole eggs, whole prey, and commercial diets.
What about vitamin D3?
If you are providing enough UVB for your sandfish skink according to the specifications on the Lighting page of this manual, your pet should be able to make all of the vitamin D3 that its body needs. However, occasionally using a low-D3 calcium supplement or multivitamin containing D3 is a reasonable way to “top up” your skink’s reserves without risk of overdose.
Supplementing vitamin D3 “instead” of using UVB lighting is not recommended. This is very dangerous, as vitamin D3 supplementation is an imprecise science at best. Supplementing D3 to replace the role of UVB in the environment requires guesswork and may provide too much or too little to the animal, depending on individual needs that can vary depending on the individual’s current health, life stage, and time of year. UVB (appropriately provided) is the best way to make sure your pet is consistently getting the perfect amount of D3 for its needs.
Using a reptile multivitamin powder supplement every once in a while is a good way to help cover any potential vitamin/mineral deficiencies in your sandfish’s diet. However, it’s easy to overdose a reptile with vitamin supplements, so when in doubt, use too little rather than too much — reptile bodies are VERY good at making do with what they have.
However, since sandfish are insectivores and unlikely to be able to convert carotene to vitamin A, they need a supplement that contains vitamin A (retinol) rather than beta carotene.
Here are ReptiFiles’ preferred reptile multivitamins for insectivores:
Use each supplement as directed by the label.
Because sandfish rely on insects for almost all of their nutrition, it is especially important to gut-load feeder insects for at least 24 hours before offering. The easiest way to keep them optimally fed and gut-loaded is with one of (or even a rotation of) the following formulas:
- Arcadia InsectFuel
- Dubia.com Dubia Diet
- Lugarti Premium Dubia Diet
- Mazuri Better Bug Gut Loading Diet
- Repashy Bug Burger
For hydration, use gel water crystals.
Some people like to use vegetable scraps to “gutload” their feeders, but personally I dislike this practice since the nutrition is incomplete and not specifically formulated for the insects’ dietary needs.
On the Subject of Water
A small water bowl should be provided, large enough for your sandfish to be able to soak its entire body if desired, but no more than an inch deep to reduce the risk of drowning. The water should be changed every day and the bowl should be scrubbed with veterinary disinfectant weekly.
Use tap, spring, or filtered water for your skink. Avoid distilled and softened water, as these aren’t very good for reptiles to drink.
- Introduction to Sandfish
- Sandfish (Scincus) Species
- Shopping List
- Enclosure Size & Cohabitation
- Lighting, Temperature & Humidity Needs
- Substrate Options
- Environmental Enrichment: Decorating the Enclosure
- Feeding Your Sandfish (YOU ARE HERE)
- Handling Tips & Behavioral Notes
- Health Information
- Additional Resources