We take a look at the freshwater fish that, through thick and thin, grace our aquariums with non-stop colour.
If there is one thing that almost everyone loves in fishkeeping, it’s colourful fish. It’s fish colour that attracted many of us to the hobby in the first place, but not all fish are colourful their whole lives, and some fish are not naturally as colourful as their domestic, line-bred relatives.
Line bred fish
These are fish whose natural counterparts carry a gene that gives them colour or pattern. Through selection by us, the parents who carry the most colour potential can be mated together to produce colourful offspring, and so on and so on until several generations on, your strain has colourful offspring all the time.
Line breeding is not new and can be used to accentuate any number of features in animals, birds, fish and plants, like in farming for example, where a dairy cow is line bred to produce more milk.
As well as colour, fish can be bred to have long fins, 'balloon' bodies – or albinos can be mated together to increase the occurrence of albino fish in future spawnings. These fish have always had the potential to be colourful, but due to natural predation, their colours have remained subtle in the wild.
Selective breeding can lead to weaker fish if not done properly, so when buying line-bred fish, always make sure that they are active, disease free and feeding well. Those that have elongated finnage as well as bright colours may become targets for other more boisterous fish. Guppies and Siamese fighters are typical examples.
In most of the fish listed, males and females have identical colour, so seek specialist help if you need to sex them. Even female Guppies now come with coloured tails, and it probably won't be long before they are produced to be as colourful as the males.
Pick of the bunch
Discus: For many aquarists, this is the ultimate aquarium fish so Discus attract a following all of their own. From the original three species of wild fish, Discus have been line bred and hybridised to produce some stunning tank-bred fish with amazing all-over body colour.
Blue diamonds offer solid, metallic blues, Pigeon bloods and Red Marlboros come in red, orange yellow and cream, and Red turquoise are exactly that. You can even buy them in pure white.
Siamese fighting fish: This line-bred fish bears virtually no resemblance to its wild counterparts and comes in a huge variety of colours and fin types. The dark solid red of a male fighter is hard to beat, nor is a rich, solid blue – and they have become so popular over the decades because of it.
Some specialist breeders also offer Butterflies, a coloured fish with a white or coloured border around the fins. Double tails, Crown tails and Half moons, an improved version of the common veiltails that we see in the shops, are also available. As for colours, take your pick from white, black, red, blue, purple, orange, gold and even a colour called mustard gas.
Molly: Another fish whose coloured variants are now far removed from its wild counterparts. Mollies are often recommended as a first fish and they come in a huge variety of colours. Golden or Saffron mollies are hard to beat if you wish to add some yellow or orange to your community tank, and the black and white Dalmatian mollies are hugely popular.
Black mollies are still one of the few jet-black fish available to us and at the other end of the scale, Silver mollies are iridescent white.
Species bred for colour
Guppy, Poecilia reticulata
Platy, Xiphophorus maculatus
Molly, Poecilia spp
Swordtail, Xiphophorus hellerii
Goldfish, Carassius auratus auratus
Siamese fighter, Betta splendens
Discus, Symphysodon spp
Koi, Cyprinus carpio
Gold severum, Heros efasciatus
Blue dwarf gourami, Colisa lalia
Golden algae eater, Gyrinocheilus aymonieri
Pink kissing gourami, Helostoma temminkii
Golden barb, Puntius sachsi
Golden angelfish, Pterophyllum scalare
Neon rosy barb, Puntius conchonius
Diamond neon tetra, Paracheirodon innesi
Golden zebra danio, Danio rerio
Gold tiger barb, Puntius tetrazona
Green tiger barb, Puntius tetrazona
Gold White Cloud Mountain minnow, Tanichthys albonubes
Gold ram, Mikrogeophagus ramirezi
Blue Jack Dempsey, Rocio octofasciata (open to debate this one as some believe it's a hybrid, others that it's natural, while other people think it was selectively bred).
The huge variety of naturally occurring coloured fish sparked off the hobby in the first place, and some fishkeepers will only ever keep wild-type fish. There are thousands of colourful species that, despite risk of predation, have evolved into truly wonderful fish. If you want out-and-out natural colour from both sexes, here are some of the best:
Clown loach, Chromobotia macracanthus
Red-tailed black shark, Epalzeoryhnchos bicolor
Serpae tetra, Hyphessobrycon callistus
Cardinal tetra, Paracheirodon axelrodi
Neon tetra, Paracheirodon innesi
Golden nugget plec, Baryancistrus sp. L18, L81, L177
Zebra plec, Hypancistrus zebra, L46
Goldy plec, Scobinancistrus aureatus, L14
Blue phantom plec, Hemiancistrus sp. L128
Green plec, Hemiancistrus subviridis, L200
Ram, Mikrogeophagus ramirezi
Boesemani rainbow, Melanotaenia boesemani
Midas cichlid, Amphilophus citrinellus
Crenicichla sp. "Xingu 1"
Tropheus sp. "Ikola"
Siamese tiger fish, Datnioides microlepis
Pearl stingray, Potamotrygon sp. “Pearl” R080
Leopoldi stingray, Potamotrygon leopoldi
Henlei stingray, Potamotrygon henlei
Black ghost knifefish, Apteronotus albifrons
Fire eel, Mastacembelus erythrotaenia
Asian arowana, Scleropages spp.
Banded leporinus, Leporinus fasciatus
Pick of the bunch
Cardinal tetra: This fish needs no introduction and is an iconic tropical fish. More colourful than the Neon tetra, the Cardinal is graced with an iridescent blue/green top half and rich red all long the belly region and tail. Females grow slightly larger than males. The more you add (water quality allowing), the better they will be.
Boesemani rainbow: This fish still isn’t as popular as it should be, perhaps because of its relatively high price. With a body divided vertically into blue at the front and yellow at the back, a mature Boesemani rainbow can rival marine fish for colour and makes a perfect addition to the medium-large community tank. A well-decorated tank combined with good food can make the already colourful Boesemani into a show fish, and they have few if any flaws.
Rainbowfish are quite late developers compared to some other species, so save up, buy a group, sit back and wait – the colours of this fish will truly blossom.
Neolamprologus leleupi: I picked this one because it is possibly the most gaudy, naturally coloured fish from Lake Tanganyika and it can make a great cichlid addition to the right tank. Adult at 8-10 cm/3-4”, and with bright yellow males and females, leleupi are not beyond the capabilities of anyone. Given a 90 cm/3’ tank, plenty of rock work and well-filtered hardwater, they are quite easy to keep.
Their colours can be altered slightly due to foods and aquarium terrain. Keep them over coral sand and bright ocean rock and they turn a light, lemon colour. Keep them over black sand, dark rocks and feed them plenty of Spirulina foods and they can turn a dark orange.
The fish are probably happier over darker substrates and rocks, so the latter method is preferable.
Pseudotropheus demasoni: We all know and love the Yellow labidochromis, so I’ve highlighted another Malawi stunner instead. Pseudotropheus demasoni does turn up in more specialised Malawi cichlid shops, and when it is stocked, creates a lot of interest. Both the male and female are covered in dark blue, almost black vertical stripes over a light blue body.
They stay small at around 8 cm/3” total length, and when kept with fish like Yellow labs, the clash of blue and yellow can look superb. Being mbuna they are rock-dwelling, and their vertical stripes are similar to male Pseudotropheus saulosi or Pseudotropheus elongatus "Mpanga". In smaller tanks, the three species are best kept apart.
Fire eel: If you have a big tank, this is a stunning oddball. The Fire eel can reach lengths of 1 m/39”, but few top 60 cm/24”, and they become broader as they mature. The orange/red stripes and spots over a slate-grey body make it a popular fish and if you can master feeding it (usually a combination of hand feeding flake and dropping frozen foods to it), it is straightforward to keep. Give it a long pipe to hide in and you are away.
L-nos: What lucky people we are when even our bottom-dwellers are adorned with colour and pattern. The past 20 years or so have seen the discovery of hundreds of species of Loricariids, and many are well worth of the world’s most colourful tropical fish list.
Personal favourites include the Golden nugget L18, the Snowball plec LDA33 and, of course, the Zebra plec L46, which is now thankfully being captive bred in significant numbers.
The only downside is that they often hide, so research their habitat requirements thoroughly and offer plenty of food, and they should feel more at home and venture out more regularly.
Red-tailed black shark: I picked this one because it’s a great-looking fish that is often misunderstood. If this was a new species, this bi-coloured 'shark' would sell for hundreds of pounds. Instead, it has been in the hobby for decades and is one of the most popular fish in the shops. The unfortunate downside is that it is territorial and won’t tolerate other 'sharks' or similarly shaped or coloured fish in the same tank.
The answer is to keep just one in a large, well-decorated tank with other fish that it won’t see as a threat. These should ideally be totally different looking and swimming at a higher level.
Give it room to forage and no cause to get upset and it will mature into a wonderful, jet-black fish with a crimson tail and a white tip on the dorsal fin. Mature RTBS are well worthy of the most colourful fish list.
Colourful male, drab female
It is the way in nature that often the male becomes showier or more colourful in order to attract a mate, and this applies to hundreds of species of aquarium fish. Wherever possible, I believe that males and females of the same species should be kept together in order for them to communicate, interact and enrich their lives.
This can cause issues when stocking in some situations as you may be required to stock more females than males, and you may not want the grey or brown females who accompany the males.
As this is the most colourful fish list, pale other halves do lose them points, but in terms of male colour, there are some world beaters.
So much colour:
Rosy barb, Puntius conchonius
Cherry barb, Puntius titteya
Black ruby barb, Puntius nigrofasciatus
Golden wonder, Aplocheilus lineatus
Endler, Poecilia wingei
Wild guppy, Poecilia reticulata
Paradise fish, Macropodus opercularis
Honey gourami, Colisa chuna
Dwarf gourami, Colisa lalia
Electric blue hap, Sciaenochromis fryeri
Red rainbow, Glossolepis incisus
Dwarf neon rainbow, Melanotaenia praecox
Pick of the bunch
Nothobranchius rachovii: If these fish were a bit easier to keep, more widely available and had colourful females, I am sure that they would be right up there with Cardinal tetras as some of the world’s most popular colourful fish.
There are no two ways about it, the male is an absolute cracker. Bright orange with metallic blue plastered all over its body, this could rival any marine fish for colour.
Sadly they are not perfect for community tanks, but I have had long-term success when they were placed into a small, softwater tank with a pair of Peacock gobies. If they come into your local shop, grab them before they deteriorate in unsuitable conditions.
Sciaenochromis fryeri/ahli: Known for years as Haplochromis ahli or the Electric blue hap, male S. fryeri are one of the bluest fish available for freshwater. Unlike many Malawi haps, once the male turns blue, it tends not to turn its colour off again, even in the presence of other more dominant fish. It makes an excellent display fish and, like the demasoni, if mixed with the bright yellow but relatively peaceful Yellow lab, the yellow-blue clash can look really good and even marine-like.
Just to confuse you even more, the original H. ahli still exists as Sciaenochromis ahli, and in both cases, the females are a drab grey colour.
Beautiful males and drab females are a trait of all the former Malawi haps and the true Lake Victoria Haplochromis, Astatotilapia and Pundamilia. There are hundreds of species to choose from.
Endler: When I worked in aquatic shops, I had a hard job trying to stop people from picking all of the males and leaving me with the drab females. The Endler, now properly named Poecilia wingei, is similar to a wild Guppy, but is a species in its own right.
Close up the tiny male fish are virtually unrivalled with neon stripes over red, black, white and yellow, and some individuals have neon stripes right into the tail fin. There are loads of variation between batches, and they are being line bred to create some stunning patterns like Tiger’s Endlers. Great for nano tanks.
How to make your fish more colourful
There are lots of ways to improve the colour of the fish in your aquarium.
One of the best ways is simply to change the lighting. Choose a light tube that has been designed to enhance a fish’s natural colour. Colour-enhancing tubes will highlight blues and reds, and normally have quite a pink hue when they are on. If you have very bright lighting, it may make a fish turn quite pale and inconspicuous. Lower levels of lighting may cause colours to intensify.
Adding rocks, bogwood and a few plants will turn a bare tank into a home for your fish, and with the extra security that the hiding places provide, fish will feel safer and may show more colour.
Dark gravel and décor will show off much more intense colours than light ones, and natural colours are better for fish than unnatural hues, like pink for example. For a good-looking tank, use muted, natural décor like browns, greys and black. This will complement the bright colours of the fish and not detract from them.
Having said this, colour schemes can work in situations where you want an aquarium to be part of a design statement, like in an office or a hairdresser’s. For instance, you could have a yellow, blue or striped theme using relevant species. Malawi cichlids work well in these situations because they are good slabs of colour, and lots of them can be mixed in the same tank. Single-species tanks of Tropheus can look understated but classy.
In fact, lots of colourful species look fantastic as single-species displays. Imagine a large tank full of Cardinals, Discus the size of saucers or Angelfish. Guppies look so good in shops because hundreds are kept in the tank, making an eye-catching display. Stock 30 or 40 males in a large tank with no other fish and they will not only look good, but they won’t get nibbled by anything and hopefully won’t catch disease from any other fishy sources.
Not to my taste, but some people I know prefer to keep only albinos. There are loads to choose from these days, and the fact that they all have impaired sight may make them better matches than being slung into the average community tank.
Keeping them happy
Fish will always be happier and behave more naturally when given the right water conditions. A happy wild-type fish will also be more colourful in water of the right pH and temperature, as well as when given water that is low in pollutants.
Rams from South America are a classic example, only showing great colour when kept in water that is warmer and softer than normal.
Conditioning a fish with foods will go a long way to improving its colour. To start with, try varying its diet and provide foods of the right size and consistency like what they would get in the wild. Vary dry foods and alternate with a selection of frozen foods, freeze-dried and occasional live.
Colour foods are available and will help to slightly improve the colour of most fish. Spirulina algae-based foods can improve the colours of grazers like Malawi mbuna, while colour-enhancing flake and crisps can help a red fish to maintain bright colour. Lobster and oyster eggs are also said to improve colour in fish.
Here are some fish that, given the right size tank and budget, are also eye-catching, colourful and worthwhile fish to add colour and pattern to your tank.
First is the Tiger striped catfish, Brachyplatystoma tigrinum, a large Pimelodid that tops at about 60 cm/24”. As catfish go it looks pretty exotic with its shovelnose and elongate striped body.
Next are the stingrays, of which many species feature on the list including the spotted Leopoldi, Henlei, P14, and the ringed Pearl ray. Tank bred is the way to go.
Then there's the Dragon fish or Asian arowana. Several species of Asian arowana were farmed due to decreasing numbers and a Cites listing, and this started a craze of keeping them in aquaria.
Scleropages legendrei is one of the wild-type Asians referred to as Red or Super red arowana, but the captive-line breeding and possible hybridisation of several species places the fish on both the line-bred and wild-type lists. Either way there are some stunning fish, and several thousand pounds are needed to get you a decent one.
Possible tank set-ups
So with all the most colourful fish identified, what can we keep together? Malawi cichlids are the obvious choice, but try to keep the mbuna and haps apart in most cases. As well as being incredibly colourful, a Malawi community also gives the greatest opportunity for mixing species, and a tank full of 20 or more different cichlid species is not impossible.
Next is the Amazon tank using lots of colourful species listed above. Mix Discus, Rams, Cardinals and L-numbers for a stunning display of South America at its best. Keep the décor subdued and the rich colours will show through.
The ultimate oddball tank – and one that is popular with the more wealthy fishkeepers – is a mix of stingrays, dragonfish and catfish. In most cases the décor is kept to a minimum as the fish themselves make up the whole display.