Sunburst Tuxedo Platy (Xiphophorus maculatus)

Meet the Sunburst Tuxedo Platy, a gold and red platy in a black jacket

The Sunburst Tuxedo Platy is a colour form of the common platy, Xiphophorus maculatus, bred for the aquarium and one of the most cheerful small livebearers you can add to a community tank. Our photographs show a golden head and back, a broad black "tuxedo" jacket across the middle of the body speckled with blue-green glints, and a rear body that warms to bright orange-red through the tail base and into the tail. The dorsal fin is yellow with orange edging, and the lower fins are clear with a pale blue tint.

Underneath the colour it is a true platy: small, peaceful, easy to feed and well suited to the moderately hard to hard tap water that comes out of taps across much of the UK. Seriously Fish rates the species suitable for beginners, as long as the water is moderately hard or harder, and that is the one condition this fish will not compromise on.

Learn what the name means

Compare it with our other tuxedo and sunset platies

Breeders combine body colour and pattern freely in platies, so the same tuxedo jacket appears on several base colours. Our Red Tuxedo Platy is red all over beneath the black, while the Yellow Tuxedo Platy stays lemon-yellow. The Gold Red Tuxedo Hi-Fin Platy shares the gold-and-red idea but carries a tall, flag-like dorsal fin. If you like the warm gradient without the black, the Sunset Platy shows the plain sunset colour. All are one species with one set of care needs, and all will interbreed.

See exactly what you receive

Each purchase is one live Sunburst Tuxedo Platy of medium size: a young fish that still has some growing to do. We do not choose or guarantee sex. Males are the smaller fish and have a narrow, pointed anal fin modified into a mating organ called the gonopodium; females are larger, deeper-bodied and have an ordinary fan-shaped anal fin. The photographs show the colour form, not the individual fish, and the extent of the black jacket and the depth of the red differ from fish to fish. Expect the colours to look washed out for a day or two after the journey; they return once the fish settles.

Choose how many to order

• Three fish: the minimum group OATA recommends, ideally one male with two females.
• Six fish: a fuller, busier group with the same two-to-one ratio.
• Mixed tuxedo colours: red, yellow and sunburst tuxedos look striking together, but they will cross and the young will be a mixture.

Before you order, read our delivery and Live Arrival Guarantee details and make sure the aquarium has been running with a mature filter for several weeks.

Size the sunburst tuxedo platy aquarium correctly

Sources measure platies in different ways. OATA gives adults as 6–8 cm. FishBase records a maximum of 4.0 cm total length for males and 6.0 cm for females, and Seriously Fish gives 50 mm standard length, a measurement that stops at the base of the tail. However you measure it, you are buying a small fish whose females end up noticeably bigger than the males.

For space, OATA asks for at least 45 litres for a small group, Seriously Fish recommends a footprint of 60 × 30 cm (around 54 litres), and FishBase gives a minimum tank length of 60 cm. A 60 cm tank is therefore the sensible starting point. Remember that platies breed, and a tank that holds six adults comfortably can be holding twenty fish a few months later.

Work through a quick space plan

1. Footprint first: 60 cm long and 30 cm deep front to back as a minimum.
2. Adult numbers: plan for fish of up to 6–8 cm, not the medium youngsters that arrive.
3. Future fry: enter your tank and fish in our stocking calculator and recheck it whenever the group grows.

Furnish the tank with plants and open water

FishBase describes wild platies in warm springs, canals and ditches with slow-moving water, silty bottoms and weedy banks, as well as creeks and swamps, and Seriously Fish notes that the species appreciates a planted aquarium. Gentle flow, plenty of soft-leaved plants and a clear swimming lane at the front copy that well.

Lay out four zones

Platies pick at soft green algae on leaves and stones throughout the day, so do not scrub every surface clean. A cover glass or lid is worth having: OATA describes it as optional but advisable, and it keeps a startled fish in the tank.

Match hard, alkaline water

Seriously Fish puts it plainly: platies need moderately hard or harder water, do best with the pH above neutral and will not thrive in soft, acidic conditions. The three sources agree on pH and broadly on temperature but give quite different hardness ranges, so we show them together and recommend the overlap.

Compare the published water values

In much of England the tap water is already hard and alkaline enough for platies once it has been treated with a dechlorinator. Soft-water areas, including many parts of Scotland, Wales and the north-west, may need help to raise hardness; ask us before you buy if your water is soft. Enter your readings in our water matcher, and our guide to water chemistry explains GH, KH and pH in plain terms.

Keep the filter ahead of the fish

Seriously Fish suggests a filter that turns the tank volume over four to five times an hour, roughly 215–270 litres per hour on a 54-litre aquarium, and a heater of about 50 W where the room sits around 20°C. Platies eat steadily and breed steadily, so waste builds up faster than the number of adults suggests.

Repeat this weekly routine

1. Test ammonia, nitrite, nitrate, pH and hardness at least once a week, as OATA recommends.
2. Replace a quarter of the water each week with dechlorinated water at tank temperature.
3. Vacuum the gravel where droppings and uneaten food gather.
4. Squeeze filter sponges in a bucket of old tank water, never under the tap, to protect the bacteria.
5. Count the fish, fry included, so the stocking level never creeps up unnoticed.

Feed a measured, plant-rich meal

In the wild, FishBase lists worms, crustaceans, insects and plant matter in the platy's diet. Seriously Fish says it accepts frozen, live and dried foods without fuss. OATA's advice is a good-quality flake or granule with plenty of algae in it as the daily staple, fed once a day in an amount the fish clear in a few minutes, with occasional live or frozen treats.

Put together the daily portion

• Base food: an algae or vegetable flake, crumbled small for medium-sized fish.
• Treats: Daphnia, brine shrimp or bloodworm a few times a week, swapped for part of the flake rather than added on top.
• Quantity: only what disappears within a few minutes; net out anything left over.
• Young fish: Seriously Fish advises feeding fry two or three times a day on powdered flake or newly hatched brine shrimp.

Settle the fish in during the first week

Before the box arrives, check that the filter is mature, ammonia and nitrite read zero and the water sits between 20 and 25°C at pH 7.0–8.0. OATA's floating-bag method works well for platies: turn the lights off, float the closed bag for about 10 minutes, add small amounts of aquarium water to the bag over up to 20 minutes, then net the fish out and throw the bag water away rather than tipping it in. Our step-by-step acclimatisation guide shows each stage with pictures.

Follow the first-week checklist

Choose calm tank mates and a female-heavy group

Seriously Fish describes the common platy as very peaceful and suitable for most community tanks. Males tolerate one another, but they court females constantly, which is why OATA recommends at least three fish with two females to each male. The best companions are other hard-water fish of a similar size that will not bully platies at feeding time.

Check every companion

Run any planned mix through our tank mates checker. You can browse every platy fish and all livebearers we stock, or go straight to the platy category and our range of Xiphophorus maculatus platies. The platy care guide goes deeper into the group, and platies sit high on our beginner tropical fish list.

Plan for the fry that will follow

Platies are livebearers: fertilisation happens inside the female and she gives birth to fully formed, free-swimming young. FishBase gives a gestation of 24–30 days and 20–80 young per brood, with aquarium fish maturing at 3–4 months. Seriously Fish gives about four to six weeks and says broods of up to 80 fry are not unusual. A pregnant female becomes very round as the brood develops.

Raise a brood in four steps

1. Give cover: dense plants let some fry survive even in the main tank.
2. Separate the mother if you want more fry: Seriously Fish suggests moving a heavily pregnant female to a separate tank to give birth and returning her afterwards, and does not recommend breeding nets; OATA describes using a breeding net. Both aim to keep adults from eating the young.
3. Feed little and often: two or three tiny meals a day.
4. Arrange homes early: know where surplus youngsters will go before they need to leave.

Breed Sunburst Tuxedos only with one another if you want young that look like their parents. Crossing with other colours gives a mixed brood, and the tuxedo jacket is not always passed on in the same shape.

Watch for health warning signs

Seriously Fish warns that many commercially produced platies are less hardy than they should be because of inbreeding and over-production, which makes stable water and a calm settling-in period important. OATA's warning signs include clamped fins, flicking or shaking, hanging at the surface or lying on the bottom, unusually dark or pale colour, white spots or fluffy growths, lost fins or scales, faster or slower breathing and a poor appetite.

Link each sign to an action

The black pigment of the tuxedo pattern has a scientific history. A review by Meierjohann and Schartl (2006) explains how certain crosses between platies and swordtails develop melanoma, a pigment-cell tumour, which has made these fish a research model for many decades, and FishBase notes that the species is used in genetic research. For the keeper this simply means watching black areas for any change from flat colour to a raised lump. FishBase also records that at least one country reports harm after platies were introduced, so unwanted fish should go back to a shop or another keeper, never into a pond or river.

Answer Sunburst Tuxedo Platy buying questions

What is a Sunburst Tuxedo Platy?

It is an aquarium-bred colour form of the common or southern platy, Xiphophorus maculatus, a small livebearer from the Atlantic side of Mexico and Central America. "Sunburst" describes the warm colour that runs from a golden head to an orange-red tail; "tuxedo" is the platy name for the dark jacket of black pigment across the flank. Seriously Fish lists tuxedo among the established platy varieties.

How is it different from a Red Tuxedo or Yellow Tuxedo Platy?

All three carry the black tuxedo flank, but the base colour differs. A Red Tuxedo is red from head to tail and a Yellow Tuxedo stays yellow; the Sunburst Tuxedo on our photographs is golden at the front and turns orange-red behind the tuxedo patch, through the tail base and tail. Care is the same for all of them.

How big does it grow?

OATA gives adult platies as 6–8 cm. FishBase records 4.0 cm total length for males and 6.0 cm for females, and Seriously Fish gives 50 mm standard length, which leaves out the tail. Females are the larger sex.

What size aquarium does it need?

OATA asks for at least 45 litres for a small group of platies. Seriously Fish recommends a 60 × 30 cm base, about 54 litres, and FishBase also gives 60 cm as the minimum tank length.

What water does it need?

Hard, alkaline water. pH 7.0–8.0 suits all three sources, and 20–25°C is where OATA (17–27°C), FishBase (18–25°C) and Seriously Fish (20–26°C) overlap. Hardness figures differ: OATA 4–12°dH, FishBase 9–19 and Seriously Fish 10–30, so about 10–12 dGH satisfies all three. Seriously Fish says platies will not thrive in soft, acidic water.

How many should I keep together?

At least three, with two females for every male, as OATA advises. Seriously Fish notes that males get on with each other but can pester females relentlessly, so extra females and plenty of plants keep the group calm.

Will the black tuxedo patch change as it grows?

The size and shape of the black area differ from fish to fish and can spread or break up a little as a young platy grows, so the fish you receive will not match the photograph exactly. A flat, smooth black pattern is normal. A raised, lumpy black growth is not, and needs fish-health advice.

Will it breed in my aquarium?

Very likely, if a male and females are kept together. FishBase gives a gestation of 24–30 days and 20–80 young per brood, and aquarium platies mature at 3–4 months, so numbers rise quickly unless you plan for the fry.

How many fish come with one purchase?

One live fish of medium size. Sex is not chosen or guaranteed, and colour and pattern vary slightly from fish to fish.

Check the sources behind this guide

• Seriously Fish: Xiphophorus maculatus — maximum size, aquarium base, water values, filter and heater sizing, diet, behaviour, sexing, gestation, brood size, named varieties and the warning about inbred commercial stock.
• FishBase: Xiphophorus maculatus — maximum recorded lengths of males and females, environment values, distribution, habitat, natural diet, maturity, gestation, brood size, minimum aquarium length, IUCN status and introductions.
• OATA: How to look after swordtails & platies — UK trade-body guidance for platies and swordtails: adult sizes, tank volumes, water values, group size and sex ratio, feeding, acclimatisation, maintenance, breeding and health signs.
• Meierjohann & Schartl 2006, Trends in Genetics: From Mendelian to molecular genetics: the Xiphophorus melanoma model — peer-reviewed review of why crosses between platies and swordtails are a long-standing research model for pigment-cell tumours (melanoma).
• Tropical Fish Co delivery policy — current dispatch days and Live Arrival Guarantee terms.