Canary wrasse (Halichoeres chrysus) - Marine Aquarium Livestock UK

Decide whether this active marine wrasse fits

The Canary wrasse (Halichoeres chrysus) is a marine fish in the wrasse family, Labridae, native to the central Indo-Pacific. It suits a keeper who can maintain a mature, filtered marine aquarium, provide room for an active swimmer and assess every proposed companion carefully. FishBase records a maximum length of 12 cm total length, so plan the aquarium around that figure rather than the size of the fish when it arrives.

Wikipedia also lists golden wrasse and yellow wrasse as common names for this species. FishBase places it around reef edges and sand-and-rubble areas, usually in small groups in the wild. That natural setting explains why open swimming room, a thoughtful layout and careful social planning matter in captivity.

Keep the aquarium at 24–26°C, pH 7.9–8.3 and salinity 1.020–1.025. The temperature target is the overlap between FishBase’s recorded wild environmental range of 24–27°C and OATA’s broad group guidance for aquarium wrasses; the pH and salinity figures come from that wrasse guidance. OATA recommends at least 150 litres for one individual from a smaller wrasse species, with more space when other fish share the aquarium.

Understand the animal and the offer

One purchase supplies one live Canary wrasse. Prepare for the species’ 12 cm maximum and use adult space requirements from the beginning. This avoids treating a smaller arriving fish as a reason to use a temporary aquarium that falls below the planning floor.

Sex is guaranteed only when the selected option explicitly states male or female. This Canary wrasse listing has no sex-guaranteed option. Plan care without inferring sex from colour, size or any gallery image.

The gallery images are representative of this type of animal rather than photographs of the exact animal supplied, so colours can look slightly different from the live animal. Use the scientific name and care requirements to make the husbandry decision rather than relying on a photographed colour or pose.

What to prepare before committing

• Adult space: start with at least 150 litres for one smaller wrasse and increase the aquarium size when other species will share it.
• Water: establish 24–26°C, pH 7.9–8.3 and salinity 1.020–1.025 before introduction.
• Biological capacity: mature the filter and confirm ammonia and nitrite are both zero.
• Companions: assess temperament, adult space, water requirements and feeding access before adding the fish.
• Reef inhabitants: screen shrimp, crabs, fan worms and corals rather than assuming compatibility.

Browse the marine fish collection when comparing this wrasse with other marine animals, but make each stocking decision from the requirements of every animal already in the aquarium. A shared marine environment alone does not make two fish suitable companions.

Plan the aquarium around the adult size

Plan for a 12 cm Canary wrasse from the outset. FishBase gives that maximum as total length, and OATA places wrasses below 15 cm in its smaller-species aquarium category. For that category, use an aquarium of at least 150 litres for one individual. Treat 150 litres as a starting floor rather than a promise that every aquarium of that volume will suit every stocking combination.

Increase the planned volume when keeping the wrasse with other species. OATA explains that a larger aquarium offers more room and greater stability in temperature and water quality. The practical decision is therefore based on both the fish’s adult length and the total biological load: a nominally large aquarium can still be a poor choice if it is crowded, unstable or shaped in a way that leaves little swimming room.

Use three checks for space

1. Check adult length: use 12 cm, not the fish’s length on arrival.
2. Check the stocking plan: allow more than the one-fish planning floor whenever other animals share the aquarium.
3. Check usable room: arrange rockwork and equipment so the active wrasse can swim through the aquarium rather than being confined to a small open patch.

FishBase records this species at reef edges with sand and rubble. Reflect that natural context with a considered layout that combines structure with swimming space. OATA notes that some wrasses bury themselves when sleeping or threatened, so observe how this individual uses the aquarium and avoid treating every wrasse behaviour as identical.

A worked planning example is straightforward: one Canary wrasse begins with the OATA floor of at least 150 litres. Adding another species changes the decision, because OATA calls for an even larger aquarium when wrasses are mixed with other fish. Review the adult size, waste load, temperament and swimming needs of the whole proposed community before choosing the final volume.

Check the layout before adding livestock

Look at the aquarium as usable space rather than a volume printed on its specification. If rockwork, filtration equipment or an existing community leaves the wrasse with only a restricted open area, revise the layout or choose a larger system before introduction. Retain structured reef-edge areas while preserving routes through the aquarium for active swimming.

Repeat the space assessment whenever the stocking plan changes. A system prepared for one smaller wrasse does not remain suitable automatically after another fish is added, even when the measured water values still look stable. The extra animal changes swimming space, feeding competition and the load placed on biological filtration.

Hold marine water values steady

Keep the Canary wrasse at 24–26°C, pH 7.9–8.3 and salinity 1.020–1.025. FishBase records 24–27°C for its wild environment, while OATA gives 24–26°C for aquarium wrasses, making 24–26°C the overlap to use for routine care. OATA also gives carbonate hardness of 8–12 dKH, calcium of 380–450 ppm and magnesium of 1,250–1,350 ppm.

Ammonia and nitrite must remain at zero milligrams per litre, and nitrate should not exceed 50 milligrams per litre. These waste values are operational limits, not targets to approach deliberately. A zero ammonia result does not offset measurable nitrite, and an acceptable pH does not compensate for excess nitrate; read the test results together before deciding that the aquarium is ready.

Test before introduction, after a meaningful stocking change and whenever behaviour, breathing, colour or feeding changes. If a result sits outside the target range, correct the aquarium conditions before adding another animal. Avoid using the fish itself as a test of whether a marginal system will cope.

OATA notes that in a reef aquarium some parameters will need to be altered to accommodate more sensitive species. Set the final operating range around the needs shared by the wrasse and those inhabitants rather than changing several values abruptly. Record results consistently so a drift in temperature, pH, salinity or nitrogen waste can be identified before it becomes a visible welfare problem.

Read changes as a pattern

Compare each test with the aquarium’s recent results as well as with the stated limits. A value can remain inside the operating range while moving steadily towards an edge, so a written sequence helps distinguish one unusual reading from a continuing drift. Confirm an unexpected result and inspect filtration before making another stocking decision.

Use the complete set when assessing readiness. For example, 25°C and pH 8.1 meet their targets, but the aquarium is not ready if nitrite is measurable. Likewise, zero ammonia and nitrite do not make a system suitable when temperature, salinity or pH falls outside the instructed range.

Support the biological filter and control waste

Use a mature, well-maintained filter in every Canary wrasse aquarium. The RSPCA explains that biological filtration supports beneficial bacteria that convert toxic ammonia to nitrite and then to the safer nitrate. OATA adds that marine filtration may use live rock with sufficient water flow, an internal or external filter, or a sump-based filter. A protein skimmer can help remove dissolved organic waste before it breaks down further.

Perform a 25% partial water change at least once every week. Use a siphon where appropriate to remove settled solid waste, then test ammonia, nitrite, nitrate and pH so maintenance decisions follow measured conditions.

Clean without stripping out the filter bacteria

• Check the filter regularly and remove blockages before flow is significantly reduced.
• Do not run filter media under the tap.
• Rinse media lightly in aquarium water removed during the partial water change.
• Clean the protein skimmer regularly so it continues removing dissolved organic waste effectively.
• Return equipment to normal operation and confirm that water movement has resumed.

The reason for using removed aquarium water is to reduce the loss of the bacterial population established in the media. Chlorine or chloramine in tap water may kill those bacteria. An apparently clean filter is not an improvement if cleaning has damaged the biological process that controls ammonia and nitrite.

Match feeding and stocking changes to the filter’s capacity. OATA warns that adding fish too quickly can outpace the growth of nitrifying bacteria, producing unhealthy ammonia or nitrite levels associated with new tank syndrome. Add fish slowly, keep portions controlled and test after population or feeding increases. If ammonia or nitrite becomes measurable, stop further stocking and address water quality before making another change.

Use maintenance results to guide the next step

After cleaning, confirm that the filter and water movement have resumed before considering the task complete. Test the aquarium rather than assuming that clear-looking water means waste is controlled. Ammonia and nitrite are the decisive readings because both must remain at zero.

If flow falls again soon after cleaning, inspect for another blockage instead of repeatedly washing the biological media. If waste values rise after a new fish or feeding increase, pause further additions and restore stable results. This keeps maintenance tied to filter performance rather than to appearance alone.

Feed small portions of wrasse-appropriate food

Use OATA’s wrasse feeding guidance: offer frozen meaty foods sized so the Canary wrasse can take them cleanly. For smaller wrasses such as this one, that guidance gives frozen copepods or finely chopped krill or mysis. The correct particle size is the one the fish can eat without repeatedly dropping pieces or leaving them to decay.

Feed only what the fish can consume within a few minutes. This gives a practical portion limit: begin with a modest amount, watch the fish eat and stop adding food when interest falls or uneaten pieces remain. Remove persistent leftovers where practical because wasted food increases the load on filtration and can undermine the zero-ammonia and zero-nitrite requirement.

Judge the feeding response

• Food is too large: the fish attempts a piece but cannot swallow it; use a smaller or more finely chopped portion.
• The portion is too large: food remains after a few minutes; reduce the next portion.
• Competition is interfering: compatible tank mates take every piece before the wrasse feeds; reassess the stocking and distribution of food.
• Appetite changes: test water quality and compare breathing, swimming, colour and body condition with the fish’s normal pattern.

OATA notes that many wrasses may also accept prepared granules or flakes when these are appropriately sized. Treat acceptance as something to observe rather than assume, and keep frozen meaty foods central to the wrasse feeding plan. Vary the suitable meaty choices instead of relying on one item while maintaining the same rule on small, quickly consumed portions.

Evaluate feeding by the animal’s continuing appetite and body condition as well as by the empty food container. A fish that eats briefly but loses condition, or one that suddenly ignores a previously accepted food, needs a water-quality and health check rather than an automatic increase in portion size.

Adjust one feeding variable at a time

If pieces are repeatedly rejected, reduce their size before increasing the quantity or changing several foods together. If the wrasse eats well but food remains elsewhere in the aquarium, reduce the total portion. These separate responses distinguish a particle-size problem from overfeeding and make the next feeding easier to judge.

In a community aquarium, watch which animal actually receives each portion. A suitable food is not useful to the wrasse when faster companions take all of it. Reassess food distribution and the social combination if the fish consistently misses food, while keeping the whole meal within the few-minute portion limit.

Prepare the aquarium before introduction

Complete the aquarium checks before the Canary wrasse arrives. Confirm that the system is mature, the filter is operating properly, ammonia and nitrite are zero, and temperature, pH and salinity are within the stated ranges. This separates aquarium readiness from arrival handling: acclimatisation cannot compensate for an immature filter or unsuitable water.

Use a pre-introduction checklist

• Temperature is stable at 24–26°C.
• pH is between 7.9 and 8.3.
• Salinity is between 1.020 and 1.025.
• Ammonia and nitrite each read zero mg/l.
• Nitrate does not exceed 50 mg/l.
• The filter and water movement are operating normally.
• The aquarium begins at no less than the 150-litre planning floor for one smaller wrasse.
• Every intended companion has passed the compatibility assessment.

Increase aquarium population slowly. Beneficial bacteria need to respond whenever more fish and more feeding increase the waste load. A filter that handled yesterday’s stocking level may not immediately process a sharp rise in ammonia production, so test after additions and postpone further stocking if ammonia or nitrite appears.

Plan the first observations before release. OATA describes healthy fish as having clear, bright eyes, undamaged fins, intact scales, no ulcerations or bumps and appropriate swimming behaviour. Use the new arrival’s initial behaviour as a baseline, then watch for meaningful changes rather than reacting to one isolated movement without checking the wider pattern.

FishBase finds the species around reef edges with sand and rubble, while OATA describes wrasses as active swimmers and notes that some members of the group bury themselves. Arrange the aquarium before introduction so later alterations are not required simply to create basic swimming room. Observe the individual’s behaviour before deciding whether a particular use of shelter or substrate is normal for that fish.

Make a clear readiness decision

Proceed only when every essential check passes together. A mature filter does not compensate for unsuitable salinity, and correct temperature does not compensate for measurable ammonia or nitrite. If one reading fails, correct it and confirm stable conditions before introduction rather than relying on the remaining results.

Keep the stocking plan unchanged while assessing the new fish. Adding several animals close together makes it harder to separate a behavioural issue from a sudden increase in biological load. Slow additions also give the filter’s beneficial bacteria time to respond as feeding and waste production rise.

Follow the arrival and acclimatisation sequence

Receive the parcel in person and follow the Tropical Fish Co procedure in order. Fish are packed in oxygenated bags inside an insulated box, with a heat pack used when weather conditions call for it, and carried by a licensed live-animal courier. Keep the aquarium ready before the parcel arrives so the bag can move directly into the acclimatisation sequence.

1. Receive the parcel: live fish must not be left unattended.
2. Start filming before opening: show the sealed parcel with the outer box visible.
3. Open it in one continuous take: keep filming until the fish can be seen inside the still-sealed bag.
4. Inspect on the day it arrives: preserve the continuous video and note the fish’s condition before anything is disturbed.
5. Float the bag: leave it floating for 20–30 minutes before releasing the fish.
6. Release the fish: do not pour the bag water into the aquarium.

The video is part of the claim procedure as well as a clear record of the unopened parcel and sealed bag. If a Live Arrival Guarantee claim is needed, report it on the same day with the order number and the continuous unboxing video. Read the current delivery and Live Arrival Guarantee policy before the delivery date for the complete claim conditions.

Keep the arrival procedure separate from aquarium-water decisions. The bag-float period follows the store’s process, while the aquarium itself should already meet 24–26°C, pH 7.9–8.3, salinity 1.020–1.025 and zero ammonia and nitrite. Do not begin correcting a poorly prepared aquarium while the fish is waiting in its bag.

Prepare the sequence before receipt

Have the aquarium checks completed and the means to record the continuous unboxing ready before accepting the parcel. The first footage must show the parcel still sealed, so filming cannot be recreated after opening. Keep the fish inside the sealed bag while its condition is recorded, then continue with the 20–30 minute float.

Complete each step in order instead of interrupting acclimatisation to locate claim details or test an unprepared aquarium. The sequence protects the arrival record while allowing the fish to move from receipt to release without the bag water entering the aquarium.

Respond to health and behaviour changes

Watch for changes in swimming, colour, temperament, breathing, appearance, body condition and feeding. OATA highlights hanging at the surface, sitting on the bottom, erratic swimming, unusual hiding, darker or paler colour, altered aggression, faster or slower gill movement, white spots, fluffy growths, damaged fins or scales, weight change and reduced appetite as signs that require attention.

Begin with water testing because even small amounts of ammonia or nitrite can stress wrasses. Check ammonia, nitrite, nitrate, pH, temperature and salinity, then compare the results with the routine targets. A visible symptom and an abnormal test result should be treated as connected information rather than as separate problems.

Do not select a disease treatment from appearance alone. Several problems can produce similar changes, while poor water quality may intensify any health issue. Record test results, the timing of the change, feeding response and interactions with tank mates, then contact us for further guidance.

Continue observing after any correction. A restored test result is important, but the fish’s breathing, swimming and appetite should also move back towards its usual pattern. Keep stocking paused while the aquarium or animal remains unsettled.

Build a useful observation record

Write down what changed, when it began and whether the sign is continuous or intermittent. Pair that note with measured temperature, pH, salinity, ammonia, nitrite and nitrate, plus recent feeding and stocking changes. This gives a clearer picture than a symptom described without its water conditions or timing.

Compare several signs together. Reduced feeding alongside rapid breathing and measurable nitrite demands an immediate water-quality response, while altered hiding after a new companion also requires a social review. Continue testing and observing until both the readings and the fish’s behaviour return towards their normal pattern.

Screen fish companions carefully

OATA describes the Canary wrasse as relatively docile and says it can be mixed with more timid fish such as cardinalfish or dartfish. Treat those names as candidates for assessment, not universal pairings. The final decision must account for aquarium volume, water requirements, adult space, feeding access and the behaviour of the individuals already present.

Use a larger aquarium when mixing this wrasse with other species. The 150-litre figure applies to one individual from a smaller wrasse species, and OATA explicitly calls for more space when other species are included. Do not use the one-fish planning floor as an automatic community-aquarium recommendation.

Apply the same screening order every time

1. Water: confirm that the proposed fish can share 24–26°C, pH 7.9–8.3 and the same marine salinity plan.
2. Adult space: calculate around the Canary wrasse at 12 cm and the mature needs of every companion.
3. Temperament: favour the relatively docile context OATA describes and reject combinations that fail the behaviour assessment.
4. Feeding: make sure the wrasse can obtain appropriately sized meaty food without being excluded.
5. Observation: watch swimming, hiding, aggression, breathing and feeding after any addition.

FishBase records small groups in the wild, but aquarium group planning still depends on the space and compatibility assessment for the complete system. Ask us for a stocking and compatibility assessment before planning multiple wrasses or combining this fish with an established community.

If chasing, hiding or feeding access changes after an introduction, test the water and review the social combination together. Adding fish can affect both behaviour and biological load, so a compatibility problem and a filtration problem may appear at the same time.

Work through a candidate pairing

For a proposed cardinalfish companion, first confirm that both fish fit the same temperature, pH and salinity plan. Next, provide more than the 150-litre one-wrasse floor and assess the mature space needs of the complete community. Finally, check that both animals can feed without one excluding the other.

Apply the same sequence to dartfish rather than treating the named example as automatic approval. If the aquarium fails on water, space, temperament or feeding access, do not proceed with the pairing. After any addition, watch behaviour and test water because the social and biological changes happen together.

Make a separate reef-safety decision

Screen shrimp, crabs, fan worms and corals before placing the Canary wrasse in a reef community. OATA warns that some wrasses will eat invertebrates such as shrimp, crabs or fan worms, or nibble at corals. Ask us whether the Canary wrasse is reef safe for the shrimp, crabs, fan worms or corals you keep before adding it. Apply that warning as a reason to assess the planned combination rather than assuming that every wrasse responds identically.

A fish-to-fish compatibility result does not settle the reef question. Cardinalfish or dartfish may be reasonable fish candidates under OATA’s guidance, but that says nothing about the safety of a particular shrimp, crab, fan worm or coral in the same aquarium. Keep the two decisions separate.

For a mixed reef, identify the sensitive inhabitants first and set the aquarium around the shared water requirements. OATA notes that in a reef aquarium some parameters will need to be altered to accommodate more sensitive species, so do not change salinity, hardness, calcium or magnesium solely around the wrasse without considering the rest of the system.

After any addition, watch feeding access, hiding, aggression and visible contact with reef inhabitants. If behaviour changes, reassess the combination promptly instead of assuming that a relatively docile fish cannot create a feeding or reef-compatibility problem.

Separate the two compatibility answers

Record one decision for fish companions and another for reef inhabitants. Passing the fish assessment means the proposed companion shares suitable water, space and feeding conditions; it does not answer whether shrimp, crabs, fan worms or corals face a feeding or nibbling risk.

In a mixed reef, check the needs of the sensitive inhabitants before setting the final operating values. Then observe actual contact as well as general swimming behaviour. Repeated attention towards an invertebrate or coral requires prompt reassessment even when the wrasse remains relatively docile towards other fish.

Answer common Canary wrasse questions

How big does a Canary wrasse get?

FishBase records the Canary wrasse at up to 12 cm total length. Plan its aquarium around 12 cm from the beginning, regardless of its length on arrival.

What size aquarium does a Canary wrasse need?

OATA recommends at least 150 litres for one individual from a smaller wrasse species; the 12 cm Canary wrasse falls below OATA’s 15 cm threshold. Use a larger aquarium with other fish.

How many Canary wrasses should I keep?

FishBase records Canary wrasses in small groups in the wild. In an aquarium, decide the number through an adult-space and compatibility assessment covering the whole community.

Does this fish suit a beginner?

It suits a keeper who can maintain a mature, filtered marine aquarium, keep ammonia and nitrite at zero and make careful fish and reef compatibility decisions.

What does a Canary wrasse eat?

Follow OATA’s guidance for smaller wrasses: frozen copepods or finely chopped krill or mysis. Offer only what it eats within a few minutes.

What temperature and pH does a Canary wrasse need?

Keep the Canary wrasse at 24–26°C, the overlap of FishBase’s wild range and OATA’s aquarium wrasse range, with OATA’s pH 7.9–8.3 and salinity 1.020–1.025.

Is the Canary wrasse aggressive?

OATA describes it as relatively docile and suitable for assessment with timid fish such as cardinalfish or dartfish. Observe temperament, hiding and feeding after every introduction.

Which animals can this fish live with?

Cardinalfish or dartfish are candidates after screening. Treat shrimp, crabs, fan worms and corals with caution until the planned reef combination has been assessed.

How does this fish arrive alive?

Tropical Fish Co packs live fish in oxygenated bags inside an insulated box, using a heat pack when needed. Be there to receive the parcel, film one continuous video from the sealed parcel until the fish is visible in its sealed bag, open and inspect it the same day, float the bag for 20–30 minutes and release the fish without adding bag water.

Consult the public references

• FishBase: species identity, marine distribution, wild habitat, environmental temperature and maximum recorded length.
• Wikipedia: central Indo-Pacific origin and established common names.
• Ornamental Aquatic Trade Association: aquarium guidance for wrasses, including water, space, feeding, maintenance, health and compatibility.
• RSPCA: the role of biological filtration and beneficial bacteria in aquarium welfare.
• Tropical Fish Co delivery and Live Arrival Guarantee policy: packing, receipt, unboxing evidence and acclimatisation procedure.