Discoid Roaches vs. Wax Moth Larvae: The Honest Guide to Feeding Leopard Geckos

I've fed leopard geckos for years, and the question I get more than almost any other is some version of: "My gecko goes crazy for waxworms but barely looks at roaches — should I just feed the thing it actually likes?" The honest answer is no, and this guide is the long version of why. The two feeders in the title sit at opposite ends of the nutrition spectrum: discoid roaches (Blaberus discoidalis) are about the best everyday staple you can put in front of a leopard gecko, and wax moth larvae — better known as waxworms — are a high-fat treat that does real long-term damage when they become a habit.

I want to be clear up front about one piece of terminology, because the source material people read online uses both terms interchangeably and it confuses beginners: "wax moth larvae" and "waxworms" are the same insect. They're the larval (caterpillar) stage of the wax moth, Galleria mellonella. When a care sheet says "wax moth larvae" and your feeder cup says "waxworms," you're looking at the same fat little grub. I'll use "waxworms" for the rest of this guide since that's what you'll see on the shelf.

This is the full head-to-head: what a leopard gecko's body actually needs, the real macronutrient profile of each feeder (with the common myths corrected), the calcium-to-phosphorus problem, digestibility, the obesity and fatty-liver risk that makes waxworms genuinely dangerous in excess, the narrow situations where waxworms are legitimately the right call, how to store and gut-load each, exact feeding schedules and portions by age, and a clear verdict. Read it once and you'll never again wonder whether to "just feed the one he likes."

What a leopard gecko's body actually needs

Leopard geckos (Eublepharis macularius) are strict insectivores. In the wild, across the arid scrub and rocky grasslands of Afghanistan, Pakistan, and northwest India, they eat live invertebrates — and only live invertebrates. They don't eat fruit, they don't eat greens, and unlike a bearded dragon they never shift toward plant matter as adults. That single fact frames every feeding decision: whatever nutrition your gecko gets, it gets from bugs and from what you put on those bugs.

A healthy captive diet has to deliver four things:

• ◆Protein for muscle, growth, tissue repair, and (in females) egg production. This is the backbone of the diet, especially for fast-growing juveniles.
• ◆Fat for energy and stored reserves — but in controlled amounts. Captive geckos live in a small tank, hunt across a few feet instead of a hillside, and burn a fraction of the calories a wild gecko does. Excess dietary fat has nowhere to go but the gecko's body and liver.
• ◆Calcium, and the right balance of calcium to phosphorus, for bone density and a long list of metabolic functions. Calcium is the single most failure-prone nutrient in reptile keeping.
• ◆Vitamins, particularly vitamin D3 (so the gecko can actually metabolize the calcium it eats) and vitamin A, delivered through supplementation and gut-loading.

The two diseases that haunt leopard gecko keeping both trace straight back to this list. Metabolic bone disease (MBD) comes from too little calcium or too little usable vitamin D3 — the gecko literally leaches calcium out of its own skeleton, ending up with rubber jaw, bent limbs, and tremors. Hepatic lipidosis (fatty liver disease) comes from chronic excess fat and overfeeding — fat overwhelms the liver until it can't function. Hold those two diseases in your head, because they are exactly the lens that separates our two feeders: discoids are the answer to building a sound diet, and waxworms, fed wrong, are a direct route to the second disease.

Two more things every keeper needs baked into their routine regardless of which feeder is in the cup:

• ◆Supplementation. Because we can't perfectly replicate wild diet and sun exposure, we dust feeders with a calcium powder (often plain calcium most feedings, calcium-with-D3 on a schedule, and a reptile multivitamin periodically). Specifics depend on your lighting and your supplement brand, but some dusting routine is non-negotiable.
• ◆Gut-loading. A feeder insect is a delivery vehicle. Feed the insect well for 24–48 hours before it goes in the tank — leafy greens, squash, carrot, a quality commercial gut-load — and you pass that nutrition straight up the chain to your gecko. Feed the insect garbage and you're feeding your gecko garbage in a bug-shaped wrapper.

With that framework in place, let's profile each feeder honestly.

What discoid roaches are

Discoid roaches (Blaberus discoidalis) — sometimes called "false death's head" roaches — are a tropical roach native to Central and South America, in the family Blaberidae. Adults run about 1.5 to 2 inches with a flat, oval, glossy tan-to-brown body. For a leopard gecko you'll mostly be feeding nymphs (the immature stages) sized to your animal, with small adults for big geckos with hearty appetites.

A few traits make them a near-ideal feeder, and they're worth knowing before we get to the numbers:

• ◆They can't climb smooth walls. Adults can't grip glass or smooth plastic, so an escapee in a feeding cup or a smooth-sided tub stays put. (Worth correcting a common claim here: discoids are not "expert climbers" — that's a myth. They can grip rough surfaces like cardboard and screen, but a smooth vertical wall stops them cold.) This makes them dramatically easier and less stressful to handle than crickets, which scatter, leap, and hide in your tank.
• ◆They're soft-bodied and low in chitin. Chitin is the hard, indigestible material in an insect's exoskeleton. Discoids have a relatively soft shell, which means less chitin, easier digestion, and a lower impaction risk than harder feeders like mealworms or adult crickets.
• ◆They're quiet, nearly odorless, and hardy. No chirping, no cricket stench, and they tolerate a stockpile in a tub for weeks. They can also be bred at home cheaply, which I cover in my discoid roach keeping and breeding playbook.
• ◆They gut-load beautifully. Because they'll eat a wide range of produce and grain, you can pack them with nutrition right before feeding.

One note on legality, since people ask: discoids are popular partly because they're a legal feeder in Florida, where the more common dubia roach is restricted. Rules vary by state and change over time, so confirm your own — but for many keepers, discoids are the practical, legal staple roach.

The real nutritional profile of discoid roaches

Here's where I'll correct the source material a lot of people are working from. Discoid roaches are an excellent feeder, but they are not the calcium miracle some articles claim. Treating them as approximate, as-fed figures (real values swing with diet, life stage, and source):

• ◆Protein: ~20% (roughly 20–23% on a fresh-weight basis). High, and high-quality — this is the main reason discoids make a great staple. That protein supports growth in juveniles and maintenance in adults without dragging a lot of fat along with it.
• ◆Fat: ~6–7% (roughly 5–8%). Moderate-to-low, and this is the killer feature. A lean feeder lets you feed regularly without packing fat onto a gecko that doesn't burn many calories. Compare this to waxworms below and the whole argument writes itself.
• ◆Moisture: ~60% (sources range 60–75%). Reasonable hydration contribution, though leopard geckos should always have a water dish regardless.
• ◆Chitin: low, hence the good digestibility and low impaction risk.

Now the correction that matters most. A very widespread claim — repeated in the article this guide is built from — is that discoid roaches have a "favorable" or "superior" calcium-to-phosphorus ratio. That is false. Like nearly every feeder insect, discoids are phosphorus-heavy: they contain meaningfully more phosphorus than calcium, which is a poor Ca:P ratio. The target for a reptile diet is roughly 2:1 calcium-to-phosphorus, and discoids — like crickets, dubia, mealworms, and superworms — fall well on the wrong side of that line on their own.

This is not a knock on discoids. It's true of almost the entire feeder universe; the one notable exception is black soldier fly larvae (BSFL), which actually carry useful calcium. The practical takeaway is simple and important: you must dust discoid roaches with calcium before feeding. Their job is to deliver lean protein and digestible bulk; your job is to add the calcium via supplementation. Anyone who skips dusting because they read that discoids are "naturally balanced" is setting their gecko up for MBD. Don't be that keeper.

So the honest scorecard on discoids: outstanding protein, low fat, soft and digestible, easy to keep and handle, but phosphorus-heavy like everything else and therefore reliant on your calcium dusting. That combination is exactly what a staple feeder should be. When I need to restock or start a colony, I get mine from All Angles Creatures' discoid roaches, sized for both direct feeding and seeding a breeding bin.

What wax moth larvae (waxworms) are

Waxworms are the larval stage of the wax moth — usually the greater wax moth, Galleria mellonella (the lesser wax moth, Achroia grisella, is a relative you'll occasionally see referenced). In nature these caterpillars live inside beehives and eat beeswax, pollen, and honey — which tells you almost everything about their nutrition before we even look at the numbers. They're small, soft, creamy-white grubs, usually sold by the cup in bran or sawdust bedding.

Commercially, waxworms are raised on a high-energy diet of bran, glycerin, and honey to fatten them up. They are, in the most literal sense, bred to be fat. That's what makes them irresistible to geckos and what makes them dangerous as a regular food.

Their genuine virtues are real but narrow:

• ◆Extremely soft and easy to eat. No hard exoskeleton at all. A young gecko, an old gecko with worn-down teeth, or a sick gecko can eat a waxworm with almost no effort.
• ◆Highly palatable. They're sweet and fatty, and they wriggle invitingly. Geckos that have gone off their food will often take a waxworm when they'll take nothing else — genuinely useful for jump-starting a stalled appetite.
• ◆Calorie-dense. When you actually need to put weight on a gecko fast — recovery, underweight rescue, a gravid female burning reserves — that energy density is the whole point.

But every one of those virtues is the flip side of the problem.

The real nutritional profile of waxworms

Again, approximate as-fed figures:

• ◆Fat: ~20–25%. This is the headline. Waxworms are among the fattiest feeders you can buy — three to four times the fat of a discoid roach. That's not "moderately rich," it's the nutritional equivalent of feeding your gecko candy bars.
• ◆Protein: ~15–17%. Lower than discoids, despite waxworms being a "worm" people assume is protein-rich. You're getting less of the nutrient that matters most and a load of the one that does damage.
• ◆Moisture: ~60% (roughly 61–65%). Comparable to or slightly lower than a roach; nothing special for hydration.
• ◆Calcium-to-phosphorus ratio: terrible — on the order of 1:19. That is not a typo. Waxworms have a calcium-to-phosphorus ratio so lopsided toward phosphorus that they're one of the worst common feeders for bone health. Where the goal is roughly 2:1 calcium-to-phosphorus, waxworms come in around 1:19 against you. Feed them heavily without aggressive calcium supplementation and you're actively driving toward metabolic bone disease.
• ◆Fiber: very low, and the nutrient profile overall is narrow — they're an energy bomb, not a balanced food.

Put plainly: a waxworm is a high-fat, low-protein, calcium-poor grub. Calling it a "staple" or a "complete food" — both claims float around online — is simply wrong, and acting on those claims is how geckos end up obese with failing livers.

Head-to-head: the comparison table

Here's the whole argument in one view. Treat these as approximate, as-fed values; the relationships are what matter and they're reliable.

The table makes the verdict obvious, but the why behind the bottom-right cell — the risk of overusing waxworms — is important enough that it deserves its own section. This is the part most "which feeder is better" articles wave at and don't actually explain.

The real danger of waxworms: obesity and fatty liver

It's easy to read "high in fat, feed sparingly" and treat it as a soft suggestion. It isn't. Chronic overfeeding of fatty feeders like waxworms causes two linked, serious problems in leopard geckos.

Obesity. A captive leopard gecko already burns far fewer calories than a wild one. Pile on a feeder that's a quarter fat and the gecko gets fat fast — you'll see it as bulging armpits ("calorie sacs" or fat pads under the front legs), a belly that hangs, and a thick tail that goes from healthy-plump to bloated. Obesity in reptiles isn't cosmetic: it reduces mobility, stresses organs, complicates breeding, and shortens lifespan.

Hepatic lipidosis (fatty liver disease). This is the one that kills. When a gecko takes in more fat and calories than its liver can process and store properly, fat accumulates in the liver cells themselves until the organ can no longer do its job. The liver is central to metabolism, so liver failure cascades into appetite loss, lethargy, weight loss despite the fat reserves, and death. It's a well-recognized condition in captive reptiles and a known consequence of inappropriate, fat-heavy diets — the kind built on too many waxworms. The Merck Veterinary Manual's reptile nutrition material is a good non-commercial starting point on how diet drives these metabolic and nutritional disorders (Merck Veterinary Manual: Nutrition in Reptiles).

And there's a third, sneakier problem that makes the first two worse:

Waxworm addiction. Because they're so palatable, geckos that get waxworms regularly often start refusing healthier feeders, holding out for the junk food. I've seen geckos go on hunger strikes against perfectly good roaches because they'd been trained to expect candy. Now you're stuck: the gecko won't eat its staple, so you cave and feed more waxworms, which deepens both the addiction and the obesity. The way out is exactly the way you'd break a kid of a sugar habit — stop offering the treat, hold the line, and let hunger reset the palate. Far better to never create the dependency in the first place.

Layer in the 1:19 calcium-to-phosphorus ratio and a waxworm-heavy diet becomes a triple threat: fat, calcium-poor, and addictive. That's the case against making them anything but a rare treat, and it's why "just feed the one he likes" is bad advice.

When waxworms are actually the right call

I want to be fair to waxworms, because "treat" doesn't mean "useless." There are real situations where that energy density is exactly the tool you want, and a good keeper has them in the toolbox:

• ◆An underweight or recovering gecko. After illness, parasite treatment, a hard shed problem, or a rough move, a thin gecko needs to regain weight and strength. The fat in waxworms is genuinely useful here as a short-term calorie boost — under a plan, with a target weight, not forever.
• ◆A gravid (egg-laying) female. Egg production is metabolically expensive. A few extra waxworms can help a breeding female keep condition through the drain of producing eggs — alongside, critically, heavy calcium support, because egg-laying pulls hard on her calcium reserves.
• ◆Jump-starting a stalled appetite. A gecko that's gone off food (post-move stress, brumation grogginess, a finicky individual) will often take a waxworm when it refuses everything else. Use it to get the gecko eating again, then transition back to staples.
• ◆Picky-eater coaxing — carefully. You can sometimes use a waxworm to get a stubborn gecko interested, then wean back. The risk is obvious (addiction), so this is a tactic, not a routine.

The common thread: waxworms are a short-term, purpose-driven intervention, not a baseline. A healthy adult gecko in good weight doesn't need waxworms at all. If you want to give the occasional treat anyway, that's fine — just keep it occasional, dust it like everything else, and watch the gecko's body condition.

Calcium, phosphorus, and supplementation — the part you can't skip

Because I corrected a big myth above, let me lay out what's actually true and what to do about it, since this is where geckos live or die.

Every reptile keeper is working toward a roughly 2:1 calcium-to-phosphorus intake. The reason it's a ratio and not just "give calcium" is that excess phosphorus actually interferes with calcium absorption — so a phosphorus-heavy feeder doesn't just fail to provide calcium, it works against the calcium you do supply. That's why a feeder's Ca:P matters, not only its raw calcium.

Here's the reality across feeders:

• ◆Almost every feeder insect is phosphorus-heavy. Crickets, dubia, discoids, mealworms, superworms, and especially waxworms all have poor Ca:P on their own. This is normal, and it's why dusting exists.
• ◆The exception is black soldier fly larvae (BSFL), which carry genuinely useful calcium and are the one feeder you'll hear called "naturally balanced" with any honesty.
• ◆So the correction for discoids and for waxworms is the same: dust with calcium. Discoids start from a better baseline (lean, high-protein, merely phosphorus-heavy); waxworms start from a far worse one (~1:19 Ca:P plus a fat overload). Dusting helps both, but it can't turn a junk-food grub into a staple — it just makes an occasional waxworm less harmful.

A workable supplement routine for most keepers looks like:

• ◆Plain calcium (no D3) on most feedings — a light dusting in a feeding cup, shaken so the feeder is lightly coated.
• ◆Calcium with D3 on a schedule (how often depends on whether you provide UVB lighting; geckos kept without UVB lean more on dietary D3). Follow your supplement's guidance and don't double up to the point of vitamin toxicity.
• ◆A reptile multivitamin periodically for vitamin A and trace nutrients that dusting and gut-loading miss.

Gut-loading reinforces all of this: a feeder that's been eating calcium-rich, nutrient-dense food for a day or two before it's offered carries more of that nutrition into your gecko. Dusting plus gut-loading together is how you turn a phosphorus-heavy bug into part of a balanced diet. For the deeper husbandry and care framework leopard geckos depend on overall, the University of Florida / IFAS extension reptile resources are a solid non-commercial reference.

Digestibility and impaction

Both feeders are easy on a leopard gecko's gut, which is one reason they get compared at all — but for different reasons.

Discoid roaches win on the digestibility-with-substance front. Their low chitin and soft shell mean a gecko breaks them down easily, and the impaction risk (where indigestible material blocks the gut) is low compared with hard feeders like mealworms, whose tougher exoskeletons are a bigger concern, especially for juveniles or geckos kept on loose substrate. You get the digestibility and real protein.

Waxworms are even softer — essentially no exoskeleton — so impaction risk is negligible and they're the gentlest thing you can offer a gecko with dental wear or a recovering animal. But that softness comes packaged with the fat load, so "easiest to digest" doesn't make them "best to feed." Easy to digest and good to feed are two different questions.

One universal rule that prevents most feeding problems regardless of feeder: never offer prey larger than the space between the gecko's eyes. Oversized prey is the real impaction and choking risk, far more than chitin. Size the feeder to the gecko and you've handled the biggest mechanical danger.

Feeding schedule and portions by age

Here's how I actually run it. Adjust to your individual gecko's body condition — these are starting points, not laws.

Hatchlings and young juveniles (roughly 0–4 months). Growing fast and protein-hungry. Feed daily, offering appropriately small discoid nymphs (sized to the space between the eyes) — as many as the gecko eats enthusiastically in about 10–15 minutes, often in the range of a handful of small feeders per session. Dust with plain calcium at most feedings. Waxworms: skip them, or no more than one as a rare novelty. A juvenile's job is to grow lean muscle and bone, not store fat.

Subadults (roughly 4–10 months). Slowing down a bit. Feed every other day on a staple of discoid nymphs, dusted. Waxworms: a couple, no more than once every week or two, and honestly optional.

Healthy adults (10+ months). Maintenance mode. Feed every 2–3 days, a few appropriately sized discoids per session, dusted with calcium (with D3 on schedule) and a multivitamin periodically. Waxworms: two or three once every week or two at the most — or none. A healthy adult in good weight needs zero waxworms.

Underweight, recovering, or gravid geckos. This is the window where you deliberately lean on waxworms for a calorie boost — a few per feeding, more often, alongside heavy calcium support for gravid females — until the gecko hits a healthy weight or finishes laying. Then taper back to the staple. This is a plan with an endpoint, not a new normal.

Reading body condition matters more than any schedule. A healthy leopard gecko has a plump (not bloated) tail, a flat-to-gently-rounded belly, and no bulging fat pads in the armpits. A tail thicker than the neck and puffy armpits mean back off the fat and the frequency. A skinny, sunken tail with visible hip bones means feed more (and this is where waxworms earn their keep). Let the gecko's body, not the calendar, have the final word.

Storage and handling

The two feeders could not be more different to keep on hand, and this is a genuine practical point in discoids' favor.

Discoid roaches are easy. Keep them in a smooth-sided plastic tub (they can't climb out) with cardboard egg-flats for surface area, a bit of ventilation, room-temperature warmth, dry feeder chow plus some produce for moisture and gut-loading, and they'll keep for weeks — or breed indefinitely if you want a self-renewing supply. They don't smell, don't escape, and don't die off the way crickets do. The full setup is in my discoid roach keeping and breeding guide.

Waxworms are fussier and built-to-expire. They come in a cup of bran, and the key rule is keep them cool — around 50–60°F. A wine fridge is ideal; the warmest part of a regular refrigerator works. Cold slows their metabolism, keeps them dormant, and — crucially — stops them pupating into moths. Leave them at room temperature and within a couple of weeks you'll have a cup of cocoons and then a cup of moths, which geckos won't reliably eat. Even refrigerated they don't last forever; buy small amounts you'll actually use. Before feeding, let a few warm to room temperature so they wriggle (cold, sluggish waxworms don't trigger the hunting response). Pick out any that have darkened or turned to cocoons.

Notice the asymmetry: discoids are a stockpile you can breed and basically forget about; waxworms are a perishable you keep buying. Over a gecko's life that's a real cost and convenience difference on top of the nutrition gap.

Gut-loading each feeder

Gut-loading turns a mediocre feeder into a good one and a good feeder into a great one. Twenty-four to forty-eight hours before feeding, give the insects nutrient-dense food so your gecko inherits it.

• ◆Discoid roaches gut-load wonderfully — they'll eat dark leafy greens (collard, mustard, dandelion), squash, sweet potato, carrot, and a quality commercial gut-load. This is where you push extra calcium and vitamins into the chain. Because discoids are kept easily, gut-loading is just part of the routine.
• ◆Waxworms gut-load poorly and briefly — they're near the end of their larval life and not eating much, and they're stored cold and dormant. You can offer their bran a little supplementation, but realistically you're not going to meaningfully fix their fat-heavy, calcium-poor profile through gut-loading. The honest move is to dust them with calcium right before feeding and accept them for what they are: a treat, improved a little, not transformed.

Either way, dusting happens at feeding time and gut-loading happens in the days before. Do both for staples; for waxworms, dusting is the part that counts.

Myths worth killing

A few claims circulate widely — some of them in the very article this guide improves on — that are worth correcting flatly:

• ◆Myth: "Discoid roaches have a great calcium-to-phosphorus ratio, so you don't really need to dust them." False. Discoids are phosphorus-heavy like nearly all feeders. They're a superb staple for protein and digestibility, but you must dust them with calcium. The only common feeder with naturally good calcium is black soldier fly larvae.
• ◆Myth: "Waxworms are a complete or balanced food." False. They're high-fat, lower-protein, and calcium-poor (~1:19 Ca:P). Nothing about them is "complete." They're a treat.
• ◆Myth: "If my gecko loves waxworms, that means they're good for it." False — palatability and nutrition are unrelated, and in this case inversely related. Geckos love them because they're fatty, the same reason they're bad as a staple. Preference can even become addiction.
• ◆Myth: "Soft = best for digestion = best to feed." Half-true and misleading. Waxworms are the softest feeder going, but softness only addresses impaction, not the fat and calcium problems. Discoids are plenty soft and nutritionally sound.
• ◆Myth: "Wax moth larvae and waxworms are different feeders." They're the same insect — the larval stage of the wax moth (Galleria mellonella). Different name, same grub.
• ◆Myth: "Variety means feeding lots of different treats." Variety means rotating sound staples and supplementing with occasional treats — not rotating between several fatty junk feeders. A discoid base with the rare hornworm, silkworm, or yes, waxworm, is variety done right.

Building the actual diet — putting it together

So what does a good leopard gecko diet look like in practice, with these two feeders slotted into their proper places?

The staple is a lean, high-protein feeder — discoid roaches are my top pick, with dubia roaches and crickets as solid alternatives. Everything is dusted with calcium and gut-loaded. This is 80–90%+ of what the gecko eats, full stop.

The variety rounds out micronutrients and keeps feeding interesting: the occasional silkworm (soft, decent profile), the occasional hornworm (mostly water — excellent for hydration and a treat, but can't carry a diet on its low protein), and yes, the occasional waxworm or superworm as a genuine treat. Variety should mean different sound options around a lean base, not a rotation of fat bombs.

The treats — waxworms chief among them — come out a few times a month at most for a healthy adult, or more deliberately for an underweight, recovering, or gravid gecko that needs the calories. Treats are a tool, not a meal plan.

The supplementation and gut-loading run underneath all of it: calcium on most feedings, D3 and multivitamin on schedule, feeders well-fed before they're offered. This is what actually prevents MBD and keeps the whole diet honest.

Get that structure right and the "discoid vs. waxworm" question dissolves — they're not really competing for the same slot. One is the foundation; the other is the rare indulgence.

Where these two sit among the other feeders

It helps to place discoids and waxworms in the wider lineup, because the "staple vs. treat" split isn't unique to these two — it's the organizing principle of the whole feeder shelf. Here's how the common options stack up for a leopard gecko:

• ◆Dubia roaches. Nutritionally almost interchangeable with discoids — high protein, low-moderate fat, soft, phosphorus-heavy (dust them). They're a great staple too; the choice between dubia and discoids usually comes down to legality (discoids are legal in Florida where dubia aren't) and what you can source. Either makes a fine foundation.
• ◆Crickets. A classic staple — decent protein, moderate fat, but higher chitin (a bit harder to digest), noisier, smellier, and prone to escaping and dying off. Perfectly good in rotation; I just prefer roaches for the easier keeping and softer body.
• ◆Mealworms. Convenient and cheap, but harder-shelled (more chitin, higher impaction concern, especially for juveniles) and not as protein-dense as roaches. Fine as part of variety, not my first pick for a staple.
• ◆Superworms. Like waxworms, these lean fatty (~15%+ fat) with a hard head capsule — a treat, not a staple. Useful for variety and for bigger geckos, but don't let them become the everyday feeder for the same reason as waxworms.
• ◆Hornworms. The opposite problem from waxworms: very low fat, low protein, and extremely high moisture (~85% water). They're a fantastic hydration treat and great for a gecko that needs fluids, but they can't carry a diet on so little protein. Excellent occasional item.
• ◆Silkworms. Soft, reasonably balanced, well-liked — one of the better "variety" feeders to rotate alongside a roach staple.

Slot discoids and waxworms into that picture and the lesson repeats: lean, digestible feeders (discoids, dubia, crickets, silkworms) form the base; fatty or watery specialists (waxworms, superworms, hornworms) are situational add-ons. A diet built on a roach staple with a few of these rotated in covers a leopard gecko's needs far better than leaning on any single feeder — and far, far better than leaning on the fatty one the gecko happens to beg for.

The verdict

If you came here for a straight answer: discoid roaches are the clear winner and the right everyday staple for a leopard gecko. They're high in protein (~20%), low in fat (~6–7%), soft and digestible, easy and cheap to keep (and breed), low-odor, non-climbing, and — once you've corrected the Ca:P myth and added your calcium dusting — exactly what an insectivore that doesn't burn many calories needs to eat day in and day out.

Wax moth larvae — waxworms — are a treat, and a risky one if you forget that. At ~20–25% fat, ~15–17% protein, and a brutal ~1:19 calcium-to-phosphorus ratio, they're a calorie bomb that drives obesity, fatty liver disease, and calcium deficiency when fed as anything more than an occasional indulgence — and they can hook a gecko into refusing better food. They have a real, narrow job: a short-term calorie boost for an underweight, recovering, or gravid gecko, or a lure to jump-start a stalled appetite. Used that way, they're a useful tool. Used as a regular feeder because "he likes them," they're one of the faster ways to make a gecko sick.

So build the diet on discoids, dust everything with calcium, gut-load before feeding, rotate in sensible variety, and keep the waxworms in the back of the fridge for the few times a real keeper actually needs them. Do that and you'll have a lean, bright-eyed, long-lived gecko — which is the whole point.

Want the rest of the husbandry picture? Start with my discoid roach keeping and breeding playbook for a self-renewing staple supply, and browse the full exotic animal care library for more feeder profiles and species guides.