Have you ever wondered which tropical fish are best for your tank—and which ones might turn your peaceful aquarium into an underwater boxing ring?
Tropical Fish Guide: Choosing the right tropical fish can feel like putting together the cast of a reality show. Some are chilled-out background extras, some love to stir the pot, and others might just eat the supporting cast if you’re not careful.
Whether you’re a complete beginner or a hobbyist looking to expand your aquatic empire, this is your no-nonsense guide to the UK’s most popular tropical fish species. From colourful tetras and sleek sharks to the famously dramatic Discus and belligerent Cichlids, we’ll help you find the right mix of species for your setup—without creating World War III in your living room.
Let’s dive in. (Pun absolutely intended.)
Tetras: The Peaceful Shoal Stars
Tetras like the Neon, Glowlight, Rummynose, and Cardinals are the undisputed charmers of the aquarium world. Small, peaceful, and happiest in a shoal, they’re ideal for community tanks.
- Best for: Beginners and peaceful tanks
- Water pH: 7–7.5
- Tankmates: Guppies, Corydoras, Rasboras, Shrimp
- Top picks: Neon, Glowlight, Black Widow, Rummynose, Red Eye, Penguin, Cardinal
Tetras are hardy, easy to care for, and aesthetically delightful in groups. Just avoid adding them to tanks with aggressive or nippy fish—they’re lovers, not fighters.
Freshwater Sharks: Sleek, Fast, and Territorial
Despite the name, freshwater “sharks” aren’t actual sharks—but they do have the attitude.
- Popular species: Silver Shark, Rainbow Shark, Red-Tailed Black Shark
- Caution: Can be territorial or aggressive to their own kind
- Best kept with: Other fast, robust species in large tanks
If you’re going for these stunners, space is key. These guys grow quickly and can become a menace if cramped.
Angelfish: Graceful Yet Bold
Elegant and distinctive, Angelfish can dominate the tank with their dramatic fins and proud posture.
- Ideal for: Medium to large aquariums
- Diet: Flake, frozen, and live food
- Tankmates: Larger tetras, gourami, or peaceful cichlids
They can get a bit pushy with smaller fish, so pair wisely.
Catfish: The Bottom-Dwelling Clean-Up Crew
Catfish are the hoovers of the tank—but not all are created equal.
- Types include: Pictus Catfish, Corydoras, Synodontis
- Feeding: Bottom pellets, frozen food
- Caution: Some grow huge or get boisterous
Always check their adult size. The cute juvenile could end up being the tank boss in a few months.
Gourami: The Labyrinth Lovers
Gouramis have a unique labyrinth organ allowing them to breathe air. Quirky and low-maintenance, they make fascinating tank mates.
- Top picks: Opaline, Dwarf, Pearl, and Honey Gourami
- Diet: Flakes, granules, and frozen foods
- Behaviour: Generally peaceful but can be feisty males
They add subtle elegance to any tropical tank.
Siamese Fighting Fish (Betta): One Male Per Show
Famous for their flowing fins and feisty personality, Betta fish are solo stars.
- Keep only one male per tank
- Tankmates: Avoid fin-nippers and aggressive fish
- Watch out: Those fins make them targets!
Great for nano tanks—just don’t give them roommates that’ll wreck the place.
Rainbowfish: Nature’s Neon Highlighters
Rainbowfish bring dazzling colour and active swimming behaviour to your tank.
- Best in shoals of 6+
- Top pick: Dwarf Neon Rainbow
- Diet: Mixed diet of flakes and frozen treats
Bright, quick, and social—they’re the ideal splash of colour for larger peaceful tanks.
Algae Eaters: Your Tank’s Housekeepers
These fish are practical and often adorable. But check their max size before buying.
- Small options: Ottocinclus (4–5cm), Borneo Sucker Loach (5cm)
- Heavy lifters: Bristlenose Pleco (up to 15cm), Common Pleco (up to 46cm!)
- Other algae munchers: Spotted Pleco, Gold Algae Eater, Flying Fox
Algae eating is a job—not a personality. Combine with decorative fish for balance.
Livebearers: The Baby Makers
These reproductive machines give birth to live young and are fascinating to watch.
- Common types: Guppies, Mollies, Platies, Swordtails
- Easy to breed (sometimes too easy)
- Need: Plenty of plants or hideouts for fry survival
Livebearers are colourful, low-maintenance, and great for beginners. But beware—you’ll have more fish than you bargained for before long.
Discus: The Elegant Drama Queens
Discus are beautiful and high maintenance. They need pristine water and fuss-free tankmates.
- Water: Soft, clean, slightly acidic
- Tank size: Large only
- Keep in: Groups of 5–6 minimum
- Avoid: Aggressive or overly small fish
Not beginner-friendly, but worth it for serious aquarists with time to pamper.
African Cichlids (Lake Malawi)
Known for their bold colour and even bolder personalities.
- Types: Peacock (least aggressive), Haplochromis, Mbuna (most aggressive)
- Water: 25–26°C, pH 7.8–8.6
- Tank setup: Rocky, overcrowded (to spread aggression)
- Diet: Mostly vegetarian with frozen invertebrates
A species-only tank is a must unless you enjoy underwater cage fights.
Tanganyikan Cichlids
Cichlid royalty from Lake Tanganyika. Fierce, territorial, and stunning.
- Water: 25–27°C, pH 8.2–9
- Key species: Tropheus (aggressive, mouth brooders)
- Setup: Rock-heavy, species-only tanks
- Best kept in: Colonies of 6–12 fish introduced at the same time
These are not your starter fish—but they’re absolutely show-stoppers.
Ideal Nano-Tank Fish (and Shrimp-Friendly!)
If you’ve got a small tank or shrimp colony, these are your best fishy bets:
- Galaxy Rasbora
- White Cloud Mountain Minnows (WCMM)
- Guppies
- Pygmy Cory
- Neon or Cardinal Tetra
- Threadfin Rainbow
- Glowlight Tetra
- Silvertip Tetra
- Ottocinclus
“Tropical fish aren’t just pets—they’re living art. But if you mix the wrong personalities, your masterpiece turns into a soap opera.”
Still unsure which fish are right for your tank? We’ve done the swimming so you don’t have to. Contact us for expert advice, ethical sourcing, and healthy tropical fish delivered direct.