Grasshoppers, House Flies, or Discoid Roaches: Best Feeder for Leopard Geckos?
This three-way question comes up more than you'd think, usually from leopard gecko keepers thinking about variety: grasshoppers, house flies, or discoid roaches — what's actually best? It's a useful comparison because the three feeders fail and succeed for completely different reasons, and working through it shows you exactly what to look for in any feeder.
Quick framing: leopard geckos are strict insectivores, and the quality of their insects is their diet. A good feeder needs decent lean nutrition, a way to improve that nutrition (gut-loading), a size that fits the gecko, and the practicality to source, keep, and contain it. Let's run all three through that filter.
Grasshoppers (and locusts)
In the feeder world, "grasshoppers" usually means locusts — the cultured, captive-bred form. These are genuinely nutritious: high in protein, reasonably lean, and with a soft enough body that geckos handle them well. In Europe locusts are a popular staple; in the US they're harder to get and more expensive, and many keepers default to wild-caught grasshoppers, which is where the trouble starts.
Wild grasshoppers are a real risk. They can carry pesticide residues from sprayed fields and lawns, and they're a known vector for parasites — including ones that affect reptiles. You also can't gut-load a bug you caught an hour ago. So the honest split is: cultured locusts are a fine variety feeder if you can source them; wild grasshoppers are a gamble I wouldn't take with a pet I cared about. Either way, sourcing and cost keep them out of staple territory for most US keepers.
House flies
Clean, captive-raised flies (typically hatched from cultured spikes/maggots) aren't a bad idea on the surface — they're soft, easy to digest, non-toxic, and the erratic flying movement drives leopard geckos wild, which makes them a fun enrichment feeder and a good way to tempt a bored or picky eater.
But they fall apart as anything more:
- Very low calorie. A house fly is mostly nothing. Your gecko burns energy chasing them and gets little back, so they can't carry a diet.
- Brutal to contain. They fly. Feeding flies means releasing them into the enclosure (or a feeding tub) and hoping, and any that aren't eaten become loose flies in your home.
- Short-lived and fiddly to keep in usable numbers.
- Wild flies are a hygiene hazard. House flies are classic mechanical vectors for bacteria and pathogens — never feed ones you didn't raise clean.
Verdict: a novelty/enrichment feeder at best, never a staple.
Discoid roaches
Discoid roaches (Blaberus discoidalis) are the staple the other two are measured against. Nutritionally they run roughly 20–23% protein, a lean 6–9% fat, and around 65–70% moisture — a growth-supporting profile that won't fatten a gecko.
Where they pull away from the field:
- Soft, low-chitin bodies that digest easily — good for juveniles and seniors.
- They can't climb smooth walls and don't fly — a feeding cup contains them, no escapees, the polar opposite of flies.
- Every size you need, nymphs through adults, so you size the feeder to the gecko.
- They gut-load superbly — feed the roach well and that nutrition transfers to your gecko, the biggest lever you have on feeder quality, and exactly the thing wild grasshoppers and flies don't offer.
- Easy to keep for weeks, or breed at home.
The standard caveat applies: discoids are phosphorus-heavy and need calcium dusting before feeding — true of essentially all feeders, and the reason calcium plus UVB prevents metabolic bone disease, the leading preventable illness in captive leopard geckos per the Merck Veterinary Manual on reptile nutrition.
Head to head
| Grasshoppers (locusts) | House flies | Discoid roaches | |
|---|---|---|---|
| Protein | High | Low overall calories | ~20–23% |
| Fat | Low–moderate | Very low | Low (~6–9%) |
| Gut-loadable? | Cultured: somewhat | No (short-lived) | Yes — excellent |
| Containment | Jumps | Flies — very hard | Can't climb smooth walls |
| Sourcing (US) | Hard / pricey | Niche | Easy, breedable |
| Safety risk | High if wild-caught | High if wild | Low (captive-bred) |
| Best role | Variety (cultured only) | Novelty/enrichment | Staple feeder |
Cost and value
Value isn't just sticker price — it's usable, accepted feeder per dollar. Cultured locusts are nutritious but among the pricier feeders in the US, and supply can be patchy, which undercuts their value as anything but an occasional treat. House flies are cheap to hatch from spikes but deliver almost no calories and a chunk escape uneaten, so the real cost-per-nutrition is poor. Discoid roaches are the value leader: affordable in bulk, available in every size, fully eaten, and breedable into a free-running home supply. For a keeper feeding regularly — especially across multiple geckos — nothing else comes close on cost-per-accepted-meal.
Helping a picky eater accept feeders
Whichever feeder you choose, acceptance is the goal, and a few habits help a reluctant leopard gecko:
- Feed in its hungry window — dusk into evening, when prey drive peaks.
- Lead with movement. Roach scuttle and fly flight both trigger strikes; a still feeder often gets ignored until nudged with tongs.
- Use a smooth-walled feeding cup so feeders can't hide and the gecko can focus.
- Rotate, don't fixate. Variety prevents pickiness; if a gecko is stuck on one feeder, a high-value tempt (a fly to chase, a hornworm) can reopen its appetite before you steer back to the staple.
- Give it a couple of tries before deciding a feeder is refused — new items sometimes take a second exposure.
A word on safety and risk
The single biggest safety divide here is captive-bred vs. wild-caught. Wild grasshoppers and wild flies are the two highest-risk options on this page — pesticide residues, parasites, and (for flies) mechanical transmission of bacteria are all real concerns. Captive-bred feeders from a reputable supplier let you control the input, which is the entire point of feeding deliberately. Beyond sourcing, the standard rules apply to all three: size to no longer than the width of the gecko's head to avoid choking and impaction, don't overfeed fatty or oversized prey, and dust with calcium to head off metabolic bone disease.
The verdict
Run all three through the staple filter and it's not close: discoid roaches are the best everyday feeder of the three. They're the only one that's nutritious, gut-loadable, correctly sizeable, safe, and practical all at once. Cultured locusts earn a spot as a nutritious variety feeder if you can find them. House flies are a fun enrichment feeder for picky eaters and nothing more. And wild grasshoppers or wild flies I'd skip entirely over pesticide and parasite risk.
How I'd feed a leopard gecko
- Staple: discoid roaches (or crickets) most feedings. Adults eat ~2–3 appropriately sized roaches every 2–3 days; juveniles eat smaller roaches daily. AAC carries healthy discoid roaches in sizes from hatchling nymphs to adults.
- Size every feeder to no longer than the width of the gecko's head.
- Gut-load the roaches 24–48 hours before feeding — fresh produce plus a grain/protein base.
- Dust with calcium at most feedings, plus calcium-with-D3 or a multivitamin on schedule.
- Add variety from safe sources — cultured locusts, a hornworm for hydration, an occasional fly for enrichment — never wild-caught.
- Watch the tail as your fat gauge and adjust portions from the animal.
Bottom line
Grasshoppers, house flies, or discoid roaches for a leopard gecko? Discoid roaches are the clear best choice for the core diet — safe, nutritious, gut-loadable, and easy to keep. Use cultured locusts for variety and clean flies for the occasional enrichment chase, and leave wild-caught insects out of it entirely.
Comparing more feeders? See butterworms vs. discoid roaches, the full feeder library, or breed your own staple with how to keep discoid roaches alive.