What fish are compatible with each other?

Compatible fish share similar water parameters, temperament, and size. Good combinations include: tetras with corydoras, angelfish with larger tetras, and livebearers together. Avoid mixing aggressive with peaceful species or vastly different sizes.

Can goldfish live with tropical fish?

No, goldfish require cooler water (65-72°F) while tropical fish need warmer temperatures (76-80°F). Goldfish also produce more waste and can outcompete tropicals for food. Keep them in separate, species-appropriate tanks.

What makes fish incompatible tank mates?

Incompatibility stems from: aggression levels, different temperature needs, pH requirements, size differences (big fish eat small fish), fin-nipping behavior, territorial disputes, and different dietary needs.

How many fish can I put in my tank?

The old '1 inch per gallon' rule is outdated. Consider adult size, activity level, bioload, and territorial needs. Use our compatibility checker along with the tank volume calculator for personalized stocking recommendations.

Can all community fish live together?

Not all 'community' fish are compatible. Some need specific conditions - discus require higher temperatures, some barbs are fin-nippers, and certain 'peaceful' fish become territorial when breeding. Research each species thoroughly.

What are signs of fish incompatibility?

Watch for: torn fins, missing scales, fish hiding constantly, aggressive chasing, fish not eating, stress coloration, or fish staying in one area of the tank. Remove incompatible fish immediately to prevent deaths.

Compatibility

Fish Compatibility Chart & Checker

Check aquarium fish compatibility instantly. Freshwater compatibility chart to choose peaceful tank mates and avoid aggression.

Start by selecting a fish you want to keep. Then we'll show you which other fish are compatible.

Choose Your First Fish

Select any fish to start building your aquarium

Neon Tetra

Paracheirodon innesi

Peaceful

70-81\u00B0F

pH 6-7

10+ gallons

Cardinal Tetra

Paracheirodon axelrodi

Peaceful

73-81\u00B0F

pH 5-7.5

10+ gallons

Guppy

Poecilia reticulata

Peaceful

74-82\u00B0F

pH 6.8-7.8

10+ gallons

Platy

Xiphophorus maculatus

Peaceful

70-82\u00B0F

pH 7-8.2

10+ gallons

Corydoras Catfish

Corydoras spp.

Peaceful

72-78\u00B0F

pH 6-7.5

20+ gallons

Harlequin Rasbora

Trigonostigma heteromorpha

Peaceful

73-82\u00B0F

pH 6-7.5

10+ gallons

Angelfish

Pterophyllum scalare

Semi-aggressive

78-84\u00B0F

pH 6-7.5

30+ gallons

Dwarf Gourami

Trichogaster lalius

Semi-aggressive

77-82\u00B0F

pH 6-7.5

10+ gallons

Tiger Barb

Puntigrus tetrazona

Semi-aggressive

74-79\u00B0F

pH 6-7

20+ gallons

Rainbow Shark

Epalzeorhynchos frenatum

Semi-aggressive

75-81\u00B0F

pH 6.5-7.5

50+ gallons

Betta Fish

Betta splendens

Aggressive

76-82\u00B0F

pH 6.5-7.5

5+ gallons

Convict Cichlid

Amatitlania nigrofasciata

Aggressive

79-84\u00B0F

pH 6.5-8

30+ gallons

Oscar Cichlid

Astronotus ocellatus

Aggressive

74-81\u00B0F

pH 6-8

75+ gallons

Jack Dempsey Cichlid

Rocio octofasciata

Aggressive

78-82\u00B0F

pH 6.5-7

55+ gallons

Common Pleco

Hypostomus plecostomus

Peaceful

72-82\u00B0F

pH 6.5-7.5

125+ gallons

Kuhli Loach

Pangio kuhlii

Peaceful

75-85\u00B0F

pH 6-7

20+ gallons

Black Skirt Tetra

Gymnocorymbus ternetzi

Peaceful

70-80\u00B0F

pH 6-7.5

20+ gallons

Rummy Nose Tetra

Hemigrammus rhodostomus

Peaceful

75-84\u00B0F

pH 5.5-7

20+ gallons

Ember Tetra

Hyphessobrycon amandae

Peaceful

73-84\u00B0F

pH 5.5-7

10+ gallons

Serpae Tetra

Hyphessobrycon eques

Semi-aggressive

72-79\u00B0F

pH 5-7.8

20+ gallons

Lemon Tetra

Hyphessobrycon pulchripinnis

Peaceful

72-82\u00B0F

pH 6-7.5

20+ gallons

Molly

Poecilia sphenops

Peaceful

72-82\u00B0F

pH 7-8.5

20+ gallons

Swordtail

Xiphophorus hellerii

Peaceful

72-82\u00B0F

pH 7-8.3

20+ gallons

Endler's Livebearer

Poecilia wingei

Peaceful

75-82\u00B0F

pH 6.5-8

10+ gallons

Cherry Barb

Puntius titteya

Peaceful

73-81\u00B0F

pH 6-8

20+ gallons

Gold Barb

Barbodes semifasciolatus

Peaceful

64-75\u00B0F

pH 6-8

20+ gallons

Rosy Barb

Pethia conchonius

Peaceful

64-72\u00B0F

pH 6.5-7

30+ gallons

Pearl Gourami

Trichopodus leerii

Peaceful

77-82\u00B0F

pH 5.5-7.5

30+ gallons

Honey Gourami

Trichogaster chuna

Peaceful

72-82\u00B0F

pH 6-7.5

10+ gallons

Blue Gourami

Trichopodus trichopterus

Semi-aggressive

75-82\u00B0F

pH 6-8

30+ gallons

Zebra Danio

Danio rerio

Peaceful

64-77\u00B0F

pH 6.5-7.2

10+ gallons

Celestial Pearl Danio

Danio margaritatus

Peaceful

73-79\u00B0F

pH 6.5-7.5

10+ gallons

Chili Rasbora

Boraras brigittae

Peaceful

68-82\u00B0F

pH 4-7

5+ gallons

German Blue Ram

Mikrogeophagus ramirezi

Peaceful

78-85\u00B0F

pH 5-7

20+ gallons

Bolivian Ram

Mikrogeophagus altispinosus

Peaceful

72-79\u00B0F

pH 6-7.5

30+ gallons

Kribensis

Pelvicachromis pulcher

Semi-aggressive

75-79\u00B0F

pH 5-8

20+ gallons

Firemouth Cichlid

Thorichthys meeki

Semi-aggressive

75-86\u00B0F

pH 6.5-8

30+ gallons

Electric Blue Acara

Andinoacara pulcher

Semi-aggressive

72-82\u00B0F

pH 6.5-8

30+ gallons

Otocinclus Catfish

Otocinclus vittatus

Peaceful

72-79\u00B0F

pH 6-7.5

10+ gallons

Bristlenose Pleco

Ancistrus cirrhosus

Peaceful

73-81\u00B0F

pH 6.5-7.5

20+ gallons

Panda Cory

Corydoras panda

Peaceful

68-77\u00B0F

pH 6-7

20+ gallons

Bronze Cory

Corydoras aeneus

Peaceful

72-79\u00B0F

pH 6-8

20+ gallons

Pygmy Cory

Corydoras pygmaeus

Peaceful

72-79\u00B0F

pH 6.5-7.5

10+ gallons

Siamese Algae Eater

Crossocheilus oblongus

Peaceful

75-79\u00B0F

pH 6.5-8

30+ gallons

Clown Loach

Chromobotia macracanthus

Peaceful

75-86\u00B0F

pH 6-7.5

75+ gallons

Yoyo Loach

Botia almorhae

Semi-aggressive

75-86\u00B0F

pH 6.5-7.5

40+ gallons

Boesemani Rainbow

Melanotaenia boesemani

Peaceful

75-86\u00B0F

pH 7-8

40+ gallons

Dwarf Rainbow

Melanotaenia praecox

Peaceful

75-82\u00B0F

pH 6.8-7.5

30+ gallons

White Cloud Mountain Minnow

Tanichthys albonubes

Peaceful

64-72\u00B0F

pH 6-8

10+ gallons

Glass Catfish

Kryptopterus vitreolus

Peaceful

75-82\u00B0F

pH 6.5-7.5

30+ gallons

Red Tail Shark

Epalzeorhynchos bicolor

Semi-aggressive

72-79\u00B0F

pH 6.5-7.5

55+ gallons

Silver Dollar

Metynnis argenteus

Peaceful

75-82\u00B0F

pH 6-7

75+ gallons

Fish Compatibility Checker

Select a fish to see which species are compatible tank mates

Fish Compatibility Matrix

Complete reference guide for all fish compatibility combinations. Scroll horizontally and vertically to view all species.

How to Read the Matrix

Compatible

Caution Needed

Not Compatible

Species	NT P	CT P	G P	P P	CC P	HR P	A S	DG S	TB S	RS S	BF A	CC A	OC A	JDC A	CP P	KL P	BST P	RNT P	ET P	ST S	LT P	M P	S P	EL P	CB P	GB P	RB P	PG P	HG P	BG S	ZD P	CPD P	CR P	GBR P	BR P	K S	FC S	EBA S	OC P	BP P	PC P	BC P	PC P	SAE P	CL P	YL S	BR P	DR P	WCMM P	GC P	RTS S	SD P
Neon Tetra 70-81°F \| pH 6-7
Cardinal Tetra 73-81°F \| pH 5-7.5
Guppy 74-82°F \| pH 6.8-7.8
Platy 70-82°F \| pH 7-8.2
Corydoras Catfish 72-78°F \| pH 6-7.5
Harlequin Rasbora 73-82°F \| pH 6-7.5
Angelfish 78-84°F \| pH 6-7.5
Dwarf Gourami 77-82°F \| pH 6-7.5
Tiger Barb 74-79°F \| pH 6-7
Rainbow Shark 75-81°F \| pH 6.5-7.5
Betta Fish 76-82°F \| pH 6.5-7.5
Convict Cichlid 79-84°F \| pH 6.5-8
Oscar Cichlid 74-81°F \| pH 6-8
Jack Dempsey Cichlid 78-82°F \| pH 6.5-7
Common Pleco 72-82°F \| pH 6.5-7.5
Kuhli Loach 75-85°F \| pH 6-7
Black Skirt Tetra 70-80°F \| pH 6-7.5
Rummy Nose Tetra 75-84°F \| pH 5.5-7
Ember Tetra 73-84°F \| pH 5.5-7
Serpae Tetra 72-79°F \| pH 5-7.8
Lemon Tetra 72-82°F \| pH 6-7.5
Molly 72-82°F \| pH 7-8.5
Swordtail 72-82°F \| pH 7-8.3
Endler's Livebearer 75-82°F \| pH 6.5-8
Cherry Barb 73-81°F \| pH 6-8
Gold Barb 64-75°F \| pH 6-8
Rosy Barb 64-72°F \| pH 6.5-7
Pearl Gourami 77-82°F \| pH 5.5-7.5
Honey Gourami 72-82°F \| pH 6-7.5
Blue Gourami 75-82°F \| pH 6-8
Zebra Danio 64-77°F \| pH 6.5-7.2
Celestial Pearl Danio 73-79°F \| pH 6.5-7.5
Chili Rasbora 68-82°F \| pH 4-7
German Blue Ram 78-85°F \| pH 5-7
Bolivian Ram 72-79°F \| pH 6-7.5
Kribensis 75-79°F \| pH 5-8
Firemouth Cichlid 75-86°F \| pH 6.5-8
Electric Blue Acara 72-82°F \| pH 6.5-8
Otocinclus Catfish 72-79°F \| pH 6-7.5
Bristlenose Pleco 73-81°F \| pH 6.5-7.5
Panda Cory 68-77°F \| pH 6-7
Bronze Cory 72-79°F \| pH 6-8
Pygmy Cory 72-79°F \| pH 6.5-7.5
Siamese Algae Eater 75-79°F \| pH 6.5-8
Clown Loach 75-86°F \| pH 6-7.5
Yoyo Loach 75-86°F \| pH 6.5-7.5
Boesemani Rainbow 75-86°F \| pH 7-8
Dwarf Rainbow 75-82°F \| pH 6.8-7.5
White Cloud Mountain Minnow 64-72°F \| pH 6-8
Glass Catfish 75-82°F \| pH 6.5-7.5
Red Tail Shark 72-79°F \| pH 6.5-7.5
Silver Dollar 75-82°F \| pH 6-7

Legend

PPeaceful - Community friendly

SSemi-aggressive - May chase or nip

AAggressive - Territorial or predatory

Next step

Find Your Local Fish Store

Looking for a store that carries these species? Find aquarium shops near you that can help build your 0-gallon community tank.

Find stores near me

Need help? View the step-by-step guide

Quick answer

Which aquarium fish are compatible?

Compatible fish share similar water parameters, temperament, and adult size. Peaceful community fish like tetras, corydoras, and rasboras generally work well together.

Match temperature requirements (±2°F)
Similar pH needs (±0.5)
Compatible temperaments
Consider adult sizes

Quick reference

Can bettas live with other fish?: Yes, with peaceful fish in 10+ gallons
Do angelfish eat neon tetras?: Yes, adult angels eat small tetras
Best beginner community fish?: Tetras, guppies, corydoras, platies

How to use

Step-by-step guide

Choosing compatible tank mates is crucial for a peaceful aquarium. Our fish compatibility checker helps you avoid aggressive combinations and create harmonious communities by analyzing temperament, water parameters, and size differences.

No. 01
Select your fish
Choose fish species you're interested in keeping. Start with your 'must-have' species and build around their requirements.
No. 02
Check compatibility
View the compatibility matrix showing which species work well together, which require caution, and which to avoid.
No. 03
Consider tank size
Ensure your tank is large enough for all selected species. Overcrowding increases aggression even among compatible species.
No. 04
Match parameters
Verify all species share similar temperature, pH, and hardness requirements. Parameter mismatches stress fish and cause health issues.

Pro tips

Always research individual species requirements beyond basic compatibility
Consider swimming levels — mix top, middle, and bottom dwellers for balanced communities
Add peaceful species first, then semi-aggressive ones to reduce territorial behavior
Keep schools of 6+ for schooling species to reduce stress and aggression
Have backup plans for fish that don't work out despite compatibility predictions

Quick facts

What causes incompatibility?: Aggression, different water needs, size differences, territorial behavior, and dietary requirements.
Can compatible fish still fight?: Yes — individual personalities, improper ratios, small tanks, or lack of hiding spots can cause issues.
Best beginner community?: Tetras, corydoras, and peaceful livebearers in a 20+ gallon tank make great starter communities.

Pitfalls

Common mistakes to avoid

Learn from others' errors to ensure accurate calculations and healthy aquatic life.

No. 01
Ignoring adult size differences
Why it matters — Larger fish eating smaller tank mates as they grow
Do this instead — Research adult sizes and plan for full-grown fish
No. 02
Mixing fish with different temperature needs
Why it matters — Stress, disease, and death from improper temperatures
Do this instead — Only combine fish with overlapping temperature ranges
No. 03
Overcrowding 'compatible' species
Why it matters — Aggression increases even among peaceful fish
Do this instead — Follow proper stocking guidelines and provide adequate space
No. 04
Not considering territorial behavior during breeding
Why it matters — Peaceful fish become aggressive when spawning
Do this instead — Provide extra space and hiding spots for breeding fish

Source locally

Find the gear at a local store

Find these products and services:

Products

tropical fish · aquarium decorations · live plants · fish food

Services

fish ordering · compatibility consultation

Find stores near me Browse all stores

Reference

Frequently asked questions

Next up

Building your community?

Make sure your tank is properly sized and equipped:

More calculators

Pond Volume CalculatorFish Tank Volume CalculatorAquarium Substrate Calculator - Sand & GravelAquarium Heater Size Calculator - Wattage Guide

Neon Tetra

Cardinal Tetra

Guppy

Platy

Corydoras Catfish

Harlequin Rasbora

Angelfish

Dwarf Gourami

Tiger Barb

Rainbow Shark

Betta Fish

Convict Cichlid

Oscar Cichlid

Jack Dempsey Cichlid

Common Pleco

Kuhli Loach

Black Skirt Tetra

Rummy Nose Tetra

Ember Tetra

Serpae Tetra

Lemon Tetra

Molly

Swordtail

Endler's Livebearer

Cherry Barb

Gold Barb

Rosy Barb

Pearl Gourami

Honey Gourami

Blue Gourami

Zebra Danio

Celestial Pearl Danio

Chili Rasbora

German Blue Ram

Bolivian Ram

Kribensis

Firemouth Cichlid

Electric Blue Acara

Otocinclus Catfish

Bristlenose Pleco

Panda Cory

Bronze Cory

Pygmy Cory

Siamese Algae Eater

Clown Loach

Yoyo Loach

Boesemani Rainbow

Dwarf Rainbow

White Cloud Mountain Minnow

Glass Catfish

Red Tail Shark

Silver Dollar

How to Read the Matrix

Legend

Find Your Local Fish Store

Which aquarium fish are compatible?

Step-by-step guide

Select your fish

Check compatibility

Consider tank size

Match parameters

Common mistakes to avoid

Ignoring adult size differences

Mixing fish with different temperature needs

Overcrowding 'compatible' species

Not considering territorial behavior during breeding

Find the gear at a local store

Frequently asked questions

What fish are compatible with each other?

Can goldfish live with tropical fish?

What makes fish incompatible tank mates?

How many fish can I put in my tank?

Can all community fish live together?

What are signs of fish incompatibility?

Building your community?

Fish Tank Volume Calculator

Aquarium Heater Size Calculator - Wattage Guide

Keep digging

Tank size requirements

Water parameters