Reptiles
Chinese Water Dragon
Physignathus cocincinus
Semi-aquatic emerald climber with room-sized needsAdvanced
- Lifespan
- 10-15 years, up to 20 with great care
- Size
- 60-90cm (2-3ft), roughly two-thirds tail
- Social needs
- Solitary safest; never two males
- Time
- High - daily misting, water care
- Cost
- High
- Diet
- Insectivore/carnivore, minor plant matter
Overview
What is this animal?
- The Chinese water dragon is a glossy green, semi-aquatic agamid from the forested riverbanks of Southeast Asia, spending its life climbing branches above water and diving in when alarmed.
- Males reach about 90cm (3ft) and females 60-75cm, though roughly two-thirds of that length is tail, and adults are crested, long-limbed and strikingly iguana-like.
- Despite the shared name, it is nothing like a bearded dragon: it needs tropical humidity, real vertical height and a swimming pool rather than a hot, dry desert tank.
- Juveniles are sold cheaply at 20-25cm, which hides the fact that a healthy adult lives 10-15 years (sometimes to 20) and needs a custom room-corner enclosure with filtered water.
- This is an advanced-keeper species.
- Many on the market are still wild-caught imports arriving stressed and parasitised, so seek out a captive-bred animal from a reputable breeder and expect to build its home yourself.
Temperament
- Chinese water dragons are gentler and more tractable than green iguanas, and with slow, consistent, ground-up interaction many become calm enough to hand-feed and perch on an arm.
- Taming takes months of patience, and forcing handling on a new or wild-caught animal teaches it only fear.
- They are fast, flighty prey animals whose escape reflex is to leap, sometimes straight at glass, so interaction is safest inside or directly at the enclosure rather than loose in a room.
- Their claws are sharp from climbing, and the tail can be lashed or broken and does not regrow.
- Males must never be housed together and will fight seriously, and even a male seeing his own reflection may attack the glass.
- A single dragon is the safest arrangement, with female groups possible only in very large, experienced setups.
A good fit for
- Experienced keepers ready to build a custom enclosure
- Those wanting a gentler alternative to a green iguana
- Fans of planted, bioactive, high-humidity vivariums
- Keepers home daily for misting and water changes
- People who enjoy slow, patient taming work
Common mistakes to avoid
- Snout-rubbing injuries are near-universal in small glass tanks
- No off-the-shelf vivarium is big enough for an adult
- Swimming water fouls daily and needs filtration or full changes
- Many for sale are wild-caught and heavily parasitised
- Needs the opposite of bearded dragon care despite the name
- Cheap juveniles hide a 6ft-enclosure, 15-year commitment
Enclosure
Minimum 7,200 cm² of floor (1,116 sq in) · 120 × 60 × 180 cm
Must be housed alone. Solitary safest; never two males
- An adult needs a tall, custom-built enclosure.
- A widely cited minimum is about 120x90x180cm (4x3x6ft), with the 180cm (6ft) height being the non-negotiable part, and both more floor space and more height are always better.
- A standard off-the-shelf 4ft vivarium is far too small, its lack of height alone ruling it out, so most keepers commit to a room-corner build.
- Fill that height with sturdy diagonal branches, cork trunks and dense live or artificial foliage, since these lizards perch above water and feel exposed without cover.
- A large water feature the dragon can fully submerge and swim in is essential, not optional, and should cover a substantial part of the floor.
- They routinely defecate in their water, so it needs aquarium-grade filtration or a full change every day to prevent skin and gut infections.
- Keep a basking surface of 32-35C (90-95F), warm daytime ambients of 27-30C and a cooler end around 24-26C, with a night drop that may fall to 21-24C (70-75F) but no lower.
- Hold humidity at 70-80% through twice-daily misting or an automatic mister plus the large water surface, and run strong UVB across the basking zone, using a high-output T5 tube of roughly 6% (Ferguson Zone 3) positioned so the dragon basks about 25-30cm from it.
- Cover or visually break up the lower glass, because water dragons do not perceive glass as a barrier and will rub and ram their snouts against it.
Supplies
Setup
- Enclosure
- Heating and thermostat
- UVB fixture and bulb
- Thermometers and hygrometer
- Substrate and decor
Ongoing
- Live dubia roaches, crickets and locusts
- Earthworms, silkworms or hornworms for variety
- Frozen pinky mice for occasional feeding
- Plain calcium powder without D3
- Calcium with D3 and a reptile multivitamin
- Feeder gut-load and a ventilated tub
- Long feeding tongs
- Large water bowl or basin that is easy to drain
Safe substrate: Topsoil and play sand mix · Coco fibre and coir · Cypress mulch
Care routine
Daily
- Check temperatures and humidity
- Fresh water bowl
- Look the animal over
- Mist and check humidity
- Spot-clean waste and uneaten food
Weekly
- Change the pool waterevery 2 days
- Feed to the species' scheduleevery 2 days
- Check the snout and jawevery 3 days
- Short handling sessionevery 3 days
Monthly
- Weigh-inevery 2 weeks
- Deep-clean the enclosure
- Test thermostats, lamps and guards
Less often
- Refresh the substrateevery 3 months
- Replace the UVB lampevery 6 months
Vet: Annual exam with a snout and jaw check — every 12 months (every 6 months from 8 years old)
Top resources for more info
Independent creators and organisations we would send a friend to. We have no affiliation with any of them, and nothing here is sponsored. Links checked 2026-09-19.
YouTubers
Reptiles and ResearchEvidence-led husbandry: enclosure size, UVB, thermal gradients, enrichmentClint's ReptilesWhich reptile suits you, with honest care and handling verdictsGoHerpingBeginner reptile care, setup mistakes and welfare basics
Sites
Go deeper
Diet
- Chinese water dragons are primarily insectivores, taking a varied rotation of gut-loaded dubia roaches, crickets, locusts, earthworms and black soldier fly larvae, with silkworms and hornworms as excellent lower-fat additions.
- Adults can also take the occasional vertebrate item such as a pre-killed pinky or fuzzy mouse, but these are rich treats rather than staples, and feeder fish should be offered only sparingly because many species carry thiaminase and parasites.
- Dust insects with calcium at most feedings and with a vitamin D3 supplement on a schedule, as this species is as vulnerable to metabolic bone disease as any diurnal basking lizard.
- A small amount of finely chopped greens and fruit can be offered and is sometimes eaten, but plant matter is a minor part of the diet, unlike in a bearded dragon.
- Feed juveniles daily and adults every two to three days, adjusting for body condition.
- Overfeeding rodents, waxworms and superworms produces obese, short-lived dragons.
Health
- The signature injury of this species is rostral damage: snout rubbing and nose-ramming against glass in undersized or poorly screened enclosures, leading to abrasions, jaw swelling and bone infection.
- It is so common in small tanks as to be near-universal, and the fix is space, visual barriers and planted cover, not ointment.
- Metabolic bone disease from inadequate UVB and calcium, respiratory infections from cool or dry conditions, and skin and tail infections from standing in fouled water are the other major killers.
- Wild-caught imports frequently carry heavy parasite loads, so a faecal exam with an exotics vet should follow any purchase.
- Females can produce infertile eggs without a mate and need a deep, warm lay box of moist sand-soil to avoid fatal egg-binding.
- Watch for a dull, brownish cast to the skin, sunken eyes or a kinked tail base, and find a reptile-experienced vet before you need one.
Is your enclosure big enough?
Minimum floor area7,200 cm² (1,116 sq in) of continuous, unbroken floor
As dimensions120 x 60 x 180 cm
Height180 cm minimum. This species climbs, so height is not optional.
CompanyMust be housed alone. Solitary safest; never two males
Is this urgent?
Most reptile emergencies are husbandry emergencies first. Before you panic, check the temperatures — but check them with a thermometer, not a hand.
Go now
Open-mouth breathing, or bubbles and mucus at the nose or mouthGo now. Raise the warm end to the top of the species range in transit. Respiratory infection in a reptile is usually already established by the time it is visible, and it advances fast at the wrong temperature.
NowProlapse — any tissue protruding from the ventGo now. Keep the tissue moist with clean lukewarm water. Do not push it back in. Exposed tissue dries and dies quickly, and the window for a simple repair is short.
NowGaping, gasping, or unable to right itself when gently turned overGo now. Loss of the righting reflex signals a neurological or metabolic crisis.
NowA burn, or a blackened patch on the belly or sideGo now, and unplug the heat source before you leave. Contact burns from an unregulated mat or an unguarded lamp are among the most common injuries in captive reptiles.
NowToday
Tremors, twitching, jerky limbs, or a rubbery jawCall today. Note your UVB bulb type and when it was last replaced. Almost always a calcium and D3 problem, and almost always a UVB problem underneath that.
TodayRetained shed over the eyes, or a ring of stuck shed on the tail or a toeRaise humidity and offer a damp hide, then call if it is not clear within a day. A constricting ring cuts off circulation and the digit or tail tip is lost.
TodaySudden weight loss, or a visibly sunken or triangular body shapeCall today, with the weight history. A reptile that has lost condition has usually been unwell for a while.
TodaySoon
Refusing food beyond the species' normal fastCheck what a normal fast looks like for this species before worrying — for several snakes it is weeks, not days. Then log it and book if the fast is unusual for this animal. Feeding anxiety drives more unnecessary vet visits than any other reptile question, and also masks the fasts that genuinely matter.
Check the guide firstBefore any non-emergency call, write down the four numbers a vet will ask for: the thermostat probe reading, the warm-end air temperature, the cool-end air temperature, and the hottest accessible surface. Surface temperature can run well above the air above it.
This is general guidance for a healthy adult, not a diagnosis. An exotics vet who knows your animal always overrides it — and the time to find one is before you need one.
Can a chinese water dragon eat that?
Reptile diets split hard by species. An insectivore and a grazing tortoise share almost nothing, so check the species guide as well as this list.
The full list
Never (15)
AlcoholNo safe amount at any body weight on this site.
neverAvocadoPersin. Fatal to many reptiles.
neverCaffeineCoffee, tea and energy drinks. Cardiac and neurological toxicity at tiny doses for an animal this size.
neverChocolateTheobromine and caffeine. Small mammals and reptiles cannot clear either.
neverCitrusToo acidic, and it interferes with calcium absorption.
neverDog or cat foodProtein and vitamin D levels formulated for a mammal. In tortoises it causes irreversible kidney and shell damage.
neverFirefliesLucibufagins. A single firefly has killed adult lizards. This is the most dangerous item on any reptile list and it is the one keepers do not know about.
neverFish caught from the wildThiaminase and parasite risk for turtles and aquatic species.
neverGarlicSame allium toxicity as onion, and more concentrated by weight.
neverIceberg lettuceWater with no nutrition. It fills a reptile up in place of food that would have done something.
neverLeekAllium family. Same mechanism as onion and garlic.
neverOnionOrganosulphur compounds damage red blood cells. The whole allium family is out.
neverRhubarbOxalate load high enough to cause acute kidney injury.
neverSalty or seasoned human foodSalt, oil and seasoning. Crisps, chips, seasoned leftovers and processed meat are all out.
neverWild-caught insectsPesticide residue and parasites, and the identification risk. Captive-bred feeders only.
neverRare treats (1)
WaxwormsVery fatty. Useful for a underweight animal or for medicating, addictive otherwise. One or two, rarely.
rare treatOccasional (5)
Bell pepperSafe, low oxalate, and the colour gets a refuser eating. A few small pieces a few times a week.
occasionalButternut squashWell tolerated and a useful source of vitamin A precursors. Small cubes a few times a week.
occasionalKaleGood calcium, mild goitrogen. Rotate it. Twice a week.
occasionalMealwormsHard chitin shell and a poor calcium ratio. Fine as part of a varied feed, poor as the whole diet. A few, alongside better feeders.
occasionalSpinachOxalates bind dietary calcium, which is the last thing a reptile at risk of metabolic bone disease needs. A very small amount, rarely.
occasionalEveryday foods (6)
Black soldier fly larvaeUnusually high in calcium; one of the few feeders that does not need dusting. Several per feed.
everyday foodCollard greensOne of the best staple greens for herbivorous and omnivorous reptiles. Daily.
everyday foodCricketsA standard feeder. Gut-load them for 24 hours before offering, or you are feeding an empty shell. Sized no wider than the space between the animal's eyes.
everyday foodDandelion greensExcellent calcium-to-phosphorus ratio and readily taken. Pick away from sprayed ground. Daily, for herbivorous species.
everyday foodDubia roachesBetter calcium ratio and more meat per insect than crickets, and they cannot climb glass. Sized to the animal.
everyday foodMustard greensGood calcium ratio; rotate with other greens. Several times a week.
everyday foodThat food is not on our list. Reptile diets are narrower than they look — check the species guide, and ask an exotics vet before offering anything unfamiliar.
Dust feeders with a calcium supplement to the schedule in the species guide. A reptile can be eating well and still be starving of calcium.
What it really costs
Setup, monthly, first year and across a whole life, itemised and with the electricity worked out from the actual wattage. Published figures for the same animal disagree by a factor of four, so the calculator shows ranges rather than picking one.
Bedding and substrate
Substrate choice follows the animal's natural humidity, not the look of the vivarium. Get that pairing right and most substrate arguments disappear.
Safe
Topsoil and play sand mixThe standard bioactive-ready base for arid and semi-arid species. Plain topsoil with no fertiliser, no perlite, no wetting agents.
safeCoco fibre and coirHolds humidity well for tropical species. Rinse and check it is not bone dry, which makes it dusty.
safeCypress mulchGood humidity retention for tropical snakes. Cypress specifically, not general 'wood mulch'.
safeOrchid barkLong-lasting, holds humidity, resists compaction. Common in tropical vivaria.
safePaper towel or newspaperNot attractive, but correct for quarantine, for a new arrival, and for any animal being monitored for output.
safeLeaf litter over a soil baseCover, humidity and invertebrate habitat in one. Sterilised, from a known source.
safeWith a caveat
Reptile carpetSnags claws and traps bacteria in the fibres. If used, it needs replacing rather than washing, often.
with a caveatSand alone for desert speciesReal desert is packed substrate, not loose play sand. Mix it with soil so it holds a burrow.
with a caveatBioactive setupsExcellent when established, but the clean-up crew needs weeks to establish before the animal goes in.
with a caveatNever
Calcium sand and 'digestible' sandsMarketed as safe to eat, which encourages eating it. Implicated in impaction.
neverCrushed walnut shellSharp fragments, frequently implicated in impaction, with no advantage over soil.
neverPine and cedarSame aromatic phenols as in rodent bedding, and the same airway damage.
neverUncovered heat mats and unguarded ceramic emittersNot a substrate, but the most common cause of contact burns. Every heat source needs a thermostat, and every emitter needs a guard.
neverThis is our general list for reptiles. We have not built one specific to Water Dragons yet.
Impaction is far more often a temperature problem than a substrate problem: an animal that cannot reach its digestive temperature will not pass what it swallows, whatever it is standing on.
Compare with other animals
The same axes for every animal, side by side — the way the guides are written makes that a fair comparison rather than two articles.
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