Golden Damselfish (Amblyglyphidodon aureus)

Meet the golden damselfish

The golden damselfish (Amblyglyphidodon aureus) is a vivid yellow damselfish from the reefs of the eastern Indian Ocean and western Pacific, and each purchase brings you one live fish. It grows larger than many damselfish, to a recorded 13 cm total length, so it needs a mature marine aquarium with plenty of open water, rockwork to retreat into and companions chosen with that adult size in mind.

What arrives

Each purchase is a single golden damselfish. The listing has one option and does not state a length at dispatch, so set the aquarium up for the 13 cm adult rather than for the fish in the bag. Sex is guaranteed only when the selected option explicitly states male or female. This Golden damselfish listing has no sex-guaranteed option.

The photograph shows a fish that is yellow from snout to forked tail, pictured over coral rubble in front of rockwork. Gallery images have been digitally enhanced to improve image quality. Natural colour, pattern, size and maturity can vary between live animals.

A larger damselfish than most

OATA describes chromis and damselfish as usually staying relatively small and very rarely growing over 10 cm, although some of the larger damselfish grow nearer to 15 cm. FishBase records the golden damselfish at up to 13 cm, which places it firmly among those larger species. That one fact shapes three decisions: how much water to give it, which fish share that water, and whether to keep one or several.

Why keepers choose it

OATA notes that damselfish are among the most commonly kept fish in the hobby, thanks to their bright colours, small size and hardiness. The golden damselfish delivers the colour in full, a solid golden yellow that stands out against grey rock and blue water. In the wild it feeds on zooplankton in current-swept places along steep outer reefs, a lifestyle that suits an aquarium with clear swimming space and good water movement.

Before you buy

• Your marine aquarium has matured, and ammonia and nitrite both test at zero.
• It is well above the 60-litre minimum OATA gives for a single damselfish, because this species reaches 13 cm.
• There is open swimming water in front of rockwork the fish can shelter in.
• A filter and protein skimmer are running, and you can manage a weekly partial water change.
• Your tank mates are hardy fish rather than very small or timid ones.
• You can offer small meals twice a day.

Life with a golden damselfish

Day to day, looking after this fish is a matter of rhythm rather than special equipment. Two small meals a day of flake or pellet with frozen foods, a 25% water change at least once every week, and regular tests for ammonia, nitrite and nitrate cover most of it. The rest is watching: how it swims, how it feeds and how it gets on with the fish around it.

Is it the right fish for your aquarium?

It makes most sense in an established marine aquarium with generous volume, solid rockwork and a community of hardy fish that can hold their own. It is a poorer fit for a small tank, for a community built around very small or shy fish, or for a first marine set-up that has not yet matured. If your plans include several damselfish together, start from OATA's group guidance of at least 200 litres and size up from there for a species this large.

Wild range and reef life

FishBase gives the golden damselfish a wide tropical range, from the Andaman Sea and Christmas Island in the eastern Indian Ocean east to Fiji, north to the Ryukyu Islands of southern Japan and south to the Rowley Shoals off north-western Australia and New Caledonia, with a more recent record from Tonga. Wikipedia sums this up as the central Indo-Pacific and adds a second common name, the golden sergeant. It belongs to the family Pomacentridae, which it shares with the other damselfishes and the clownfishes.

Adults live on steep outer reefs, occasionally in deep lagoons and along channel walls, usually in places exposed to current where gorgonians and long sea-whip corals grow in abundance. Juveniles gather in small groups, often among large sea fans or black corals. FishBase records a wild depth range of 0 to 60 m, usually 12 to 45 m; that is a description of where the species lives, not something a home aquarium needs to imitate.

Its wild food is zooplankton, the tiny animals that drift in open water. On the IUCN Red List it is rated Least Concern.

The damselfish family

OATA describes chromis and damselfish as fish of coral reefs all over the world, and among the most commonly kept species in the hobby. Its list of the most familiar damselfish includes the yellow tail blue damsel (Chrysiptera parasema), the domino (Dascyllus trimaculatus) and the humbug (Dascyllus aruanus), with the green chromis (Chromis viridis) the most popular chromis. The golden damselfish is a noticeably larger fish than most of them, which is why its care is worth planning on its own terms rather than by damselfish reputation.

Breeding in the wild

FishBase notes distinct pairing during breeding. The eggs are demersal, meaning they sink and stick to a surface, and they are usually laid on dead gorgonian branches, where the male guards and aerates them. This is natural history rather than a breeding plan for a home aquarium.

What the wild record means for your tank

• Current-swept reef: steady water movement through and around the rockwork is in keeping with its habitat.
• Plankton feeder: small meals, in line with OATA's twice-a-day, few-minutes guidance, fit its natural way of feeding.
• Juvenile groups, breeding pairs: a group is only worth considering in a large aquarium, which OATA puts at 200 litres or more for damselfish.
• Deep wild range: the 60 m depth record is wild context; aquarium care follows the water values in the next section.

Aquarium size and layout

Space, shelter and filtration matter more for this fish than decoration. OATA describes chromis and damselfish as relatively undemanding in terms of aquarium décor, so put the effort into volume and water quality.

How much water

The OATA chromis and damselfish care sheet advises buying an aquarium as large as possible, within reason. It recommends at least 60 litres for a single damselfish and a much larger aquarium, of at least 200 litres, to keep a group of damselfish or chromis. A larger aquarium also keeps temperature and water quality steadier.

OATA's 60-litre figure covers damselfish as a group, and most of them stay under 10 cm. For a species that reaches 13 cm, treat it as an absolute floor and give the golden damselfish considerably more room, especially if other fish will share the tank.

Rock for cover, water for swimming

In the wild, OATA explains, chromis and damselfish live near areas of hard coral growth and quickly take shelter there when they notice a threat. Recreate that with rockwork built into caves and overhangs the fish can dart into, and keep a clear stretch of open water in front of it for swimming.

Water movement

FishBase describes this species living in current-prone places on the reef, and OATA lists live rock with sufficient water flow as one way to filter a marine aquarium. Aim for steady, varied movement through the rockwork and across the open water rather than a single fierce jet.

Filtration and skimming

A filter is essential whatever the size of the tank. For marine systems OATA lists live rock with sufficient flow, an internal or external filter, or a sump-based filter, and says a protein skimmer helps by removing dissolved organic waste before it breaks down into more harmful substances. The RSPCA adds the welfare reasoning: fish produce toxic ammonia, and the bacteria in a working biological filter turn it into nitrite, also toxic, and then into nitrate, which is safer.

Heating

OATA's temperature guide for damselfish is 24–26 °C, which in a UK home means a reliable aquarium heater and a thermometer you read every day. Keep the temperature steady rather than letting it drift with the seasons.

Salinity and evaporation

Salt stays behind when water evaporates, so a marine aquarium slowly becomes saltier between water changes unless you top it up. Replace evaporated water with fresh water, not salt water, and check the salinity reading regularly against OATA's guide of 1.020–1.025. Mixing and heating replacement salt water a day ahead of each water change makes it easy to match the aquarium.

Mature first, stock slowly

Add the golden damselfish only to an aquarium whose filter has matured and whose ammonia and nitrite read zero. OATA warns that overstocking, or stocking too quickly, can lead to new tank syndrome, when there are too few nitrifying bacteria for the waste produced and ammonia and nitrite climb to levels that can make fish ill. Add fish a few at a time so the bacteria can catch up after each addition.

Water quality and weekly upkeep

OATA describes chromis and damselfish as usually undemanding of water chemistry and gives the following as a general guide for the whole group, adding that a reef aquarium may need some values altered to accommodate more sensitive species:

• Salinity: 1.020–1.025 (read as specific gravity)
• Temperature: 24–26 °C
• pH: 7.9–8.3
• Ammonia and nitrite: zero
• Nitrate: not above 50 mg per litre
• Carbonate hardness: 8–12 °dKH
• Calcium: 380–450 ppm
• Magnesium: 1250–1350 ppm

Stability over precision

These figures are for damselfish in general, so aim to keep the golden damselfish comfortably inside them and, above all, steady. A reading that holds at the same point week after week is worth more than one that swings between the edges of the range.

The weekly routine

OATA strongly recommends a partial water change of 25% at least once every week. A practical order of work:

1. Test ammonia, nitrite, nitrate and pH, and note the results.
2. Siphon out 25% of the water, lifting solid waste from the substrate as you go.
3. If the filter media needs attention, rinse it lightly in the water you have just removed. Never run it under the tap: chlorine or chloramine may kill the beneficial bacteria.
4. Clean the protein skimmer so it keeps performing.
5. Refill with prepared salt water that matches the aquarium's salinity and temperature.

In a reef aquarium

OATA's list includes carbonate hardness, calcium and magnesium alongside the basic readings, and it adds that a reef aquarium may need some parameters altered to suit more sensitive species. If the golden damselfish is going into a tank with corals, set the water around the corals' needs and check that the values still sit comfortably for the fish. A test kit that covers calcium, magnesium and carbonate hardness is worth having in that case.

Why small readings matter

OATA points out that chromis and damselfish can be stressed by even the smallest amounts of ammonia and nitrite, and that stress may then lead to disease. Nitrate is far less harmful, but it still accumulates between water changes, which is why the weekly change and careful feeding go hand in hand. Clear water tells you nothing about any of these compounds; only a test does.

Feeding a plankton picker

In the wild, FishBase records the golden damselfish feeding on zooplankton. In the aquarium, OATA describes chromis and damselfish as omnivorous fish that need a wide range of foods to be in their best health, so the aim is variety in small portions.

A balanced menu

• Base food: a good-quality flake or pellet, which OATA says will fulfil most of their nutritional needs.
• Frozen foods: mysis shrimp, enriched brine shrimp or red plankton as regular supplements. Small frozen foods like these are the nearest match to the drifting prey it eats in the wild.
• Algae: OATA notes that damselfish may also feed on algae in the wild and may graze on algae offered to herbivorous fish or growing in the aquarium.

How often and how much

OATA advises feeding chromis and damselfish only what they can eat within a few minutes, twice a day. Resist the temptation to add more: uneaten food builds up and breaks down, releasing toxic waste into the water. Portion size matters more than the brand of food.

Signs the diet is working

A well-fed golden damselfish holds a full, even body shape, keeps its bright colour and comes forward eagerly when food goes in. OATA lists weight change and reduced interest in food among the signs of a problem, so a thinning outline or a fish that ignores meals is a reason to test the water and look at the menu, not simply to feed more.

Sharing at feeding time

Watch the whole tank when you feed, not just the damselfish. If one fish crowds the rest away from food, spread the portion across the surface so every fish can reach some, and make sure herbivores still get the algae meant for them.

The first meals

A new arrival may be cautious for its first few feeds and spend time close to the rockwork. Offer a small pinch of flake or a little thawed frozen food, remove anything left after a few minutes, and try again at the next feed. Appetite usually builds as the fish settles, and a keen response at feeding time is one of the best signs that it has.

Delivery day and settling in

We hand-bag each fish in pure oxygen and pack it in an insulated poly box, adding a heat pack when the weather calls for it. The parcel travels with a tracked, licensed live-animal courier, and our email gives you the tracking number and your confirmed delivery date so you know when to be at home. You can read every condition on our delivery and Live Arrival Guarantee page.

Before the courier arrives

Get the aquarium ready before you place the order. Test for ammonia and nitrite, which should both be zero, confirm the temperature sits within 24–26 °C and the salinity within 1.020–1.025, and make sure the heater, filter and skimmer are all running. Keep a clean net and some space beside the tank ready for delivery day.

Unpacking step by step

1. Make sure someone is at the delivery address to take the parcel in, because live fish cannot be left unattended.
2. Start filming before the parcel is opened: one continuous unboxing video that begins with the sealed parcel and its outer box, recorded for every delivery.
3. Open the parcel in that same take and show the fish in its sealed bag before anything is disturbed.
4. Inspect the fish on the day it arrives.
5. Float the sealed bag in the aquarium for 20–30 minutes before releasing the fish.
6. Lift the fish out of the bag with a net and leave the bag water behind; never pour it into your tank.
7. If there is a problem, message us the same day, by WhatsApp for the fastest reply, with your order number and the video, and we will arrange a replacement or refund.

Our Live Arrival Guarantee relies on three things: someone at the address to receive the parcel, the parcel opened and inspected on the day it arrives, and a continuous unboxing video that starts with the parcel still sealed.

The first fortnight

The new fish may stay close to the rockwork for a while, which is exactly what the shelter is for. Keep meals small, watch it at each feed and check the water more often than usual during the first two weeks, since a new fish adds to the load on the filter. Hold off on further additions until it is feeding confidently, and then add any new fish gradually.

Keeping it healthy

OATA describes a healthy fish as having clear, bright eyes, undamaged fins, intact scales, no ulcerations or bumps and appropriate swimming behaviour. Get to know how your golden damselfish looks and swims on a good day; that picture is what you compare against.

Early warning signs

If you spot a change

Start with a water test, because a problem with ammonia, nitrite or nitrate is quick to confirm and often the easiest thing to correct. If a reading is out of line, carry out a partial water change and look over the filter and skimmer. Then contact us with what you have seen and your results, and we will help you work out the next step.

Hardy, but not immune

OATA counts hardiness among the reasons damselfish are so widely kept, but it also warns that they can be stressed by even the smallest amounts of ammonia and nitrite. A tough reputation buys you some tolerance for small mistakes, not a licence to skip testing, and a new aquarium that has not finished maturing remains the biggest risk to any newly added fish.

Everyday prevention

Most of what keeps a damselfish healthy is routine: stable temperature and salinity, the weekly water change, food portions it clears within a few minutes, and new fish added slowly so the filter is never overwhelmed. Feeding time doubles as a daily health check, because it is when every fish comes out and shows you how it is doing.

Tank mates and temperament

OATA stresses that damselfish vary widely in temperament: some are relatively calm and mix well with other species, while others grow large and will attack other fish. It advises checking with your retailer before mixing any damselfish with other species. With the golden damselfish, size alone puts it among the larger damsels, so plan the community around a 13 cm fish.

How damselfish temperaments differ

OATA's examples show the spread. Talbot's damsel (Chrysiptera talboti) and the yellow tail blue damselfish (Chrysiptera parasema) are among the more peaceful species and can live in a community aquarium with other hardy fish. Dominoes and humbugs sit at the other end and need much tougher companions, such as large angelfish, triggerfish and pufferfish. OATA also explains that some damselfish farm a patch of algae in the wild and defend it aggressively, which makes them territorial in aquariums. Chromis are generally quite peaceful, although they may squabble among themselves.

Where the golden damselfish fits

FishBase records the golden damselfish feeding on zooplankton on current-swept outer reefs, and notes that its males guard the eggs during breeding. Its recorded diet is plankton rather than a farmed patch of algae, but temperament still varies between individual fish, and a 13 cm damselfish is a large presence beside small, timid companions. Plan for robust, similarly hardy fish and watch the first weeks closely.

Planning the community

• Good starting point: hardy fish of similar size that hold their own at feeding time.
• Very small or timid fish: keep them out of the plan unless the aquarium is large and you can watch closely, because some damselfish will attack other fish.
• Other damselfish: OATA recommends at least 200 litres for a group, and more still for a larger species like this one.
• Tough, boisterous fish: the large angelfish, triggerfish and pufferfish that OATA matches with dominoes and humbugs are a heavy-handed choice here.
• Herbivores: damselfish may graze algae offered to herbivorous fish, so make sure grazers still get their share.

Invertebrates and corals

In the wild the golden damselfish lives among gorgonians and sea-whip corals and feeds on zooplankton. Even so, no fish can be promised to leave every invertebrate alone, so watch how it behaves around any shrimp, crabs or corals you keep. If you run a reef aquarium, remember OATA's point that some water values may need adjusting to accommodate more sensitive species.

Signs of friction

Repeated chasing, a tank mate that suddenly hides far more than before, split fins or a fish that stops coming out to feed are all reasons to act. OATA lists changes in aggression, hiding and feeding among the first signs that something is wrong, so separate a fish that is being persistently harried rather than waiting to see if it settles.

Choosing companions

As you browse our marine fish collection for companions, check each species' adult size, temperament and feeding against the points above. A shared page in the shop is not a promise that two fish will get along.

Common questions

How big does a golden damselfish grow?

FishBase records a maximum of 13 cm total length. That is larger than most damselfish, which OATA says very rarely grow over 10 cm, so plan the aquarium around a 13 cm adult.

How large an aquarium does it need?

OATA recommends at least 60 litres for a single damselfish and at least 200 litres for a group. Because this species reaches 13 cm, treat 60 litres as a bare minimum and choose a considerably larger aquarium, especially if other fish will share it.

Can I keep more than one golden damselfish?

Plan for one unless you have a large aquarium. OATA advises at least 200 litres to keep a group of damselfish, and in the wild juveniles gather in small groups while adults pair during breeding.

Is a golden damselfish suitable for beginners?

OATA notes that damselfish are among the most commonly kept marine fish, partly for their hardiness. This one suits a keeper whose marine aquarium has already matured, with zero ammonia and nitrite, and who has room for a 13 cm fish.

What does it eat?

In the wild Amblyglyphidodon aureus feeds on zooplankton. At home, offer a good-quality flake or pellet with frozen mysis, enriched brine shrimp or red plankton, feeding only what it eats within a few minutes, twice a day. It may also graze algae.

What temperature and pH does it need?

OATA's broad guidance for damselfish is 24–26 °C, pH 7.9–8.3, salinity 1.020–1.025 and carbonate hardness of 8–12 °dKH, with ammonia and nitrite at zero. These are group values, so hold the readings steady within them.

Is the golden damselfish aggressive, and will it nip fins?

Damselfish vary: some are calm, while others grow large and will attack other fish. Its recorded wild diet is zooplankton rather than a farmed patch of algae, but individuals differ, so watch for chasing or fin damage in the first weeks and separate fish if needed.

What fish and other animals can live with it?

Choose hardy fish of similar size and avoid very small or timid ones. OATA pairs peaceful damsels with hardy community fish, and tougher ones such as dominoes and humbugs with large angelfish, triggerfish or pufferfish. For a 13 cm golden damselfish, start with hardy, similarly sized fish and keep an eye on shrimp, crabs and corals as well.

How is it delivered alive in the UK?

It is hand-bagged in pure oxygen, packed in an insulated poly box with a heat pack when the weather calls for it, and carried by a tracked, licensed live-animal courier. Film one continuous unboxing video from the sealed parcel to the fish in its bag, then float the bag for 20–30 minutes before releasing it. The Live Arrival Guarantee needs that video, same-day opening and a same-day message with your order number.

Sources

• FishBase: Amblyglyphidodon aureus species summary, for distribution, wild depth and habitat, zooplankton diet, breeding biology, maximum length and IUCN status.
• Wikipedia: Amblyglyphidodon aureus, for the golden sergeant name, family placement and central Indo-Pacific range.
• OATA: How to look after chromis and damselfish, the UK ornamental fish trade association's group care sheet covering water values, aquarium size, feeding, maintenance and compatibility.
• RSPCA: fish environment, for general welfare guidance on aquarium filtration and the nitrogen cycle.
• Tropical Fish Co delivery and Live Arrival Guarantee page, linked in the arrival section, for packing, courier and claim steps.