A 55 gallon aquarium provides ample space for a variety of freshwater and saltwater fish. The key considerations when stocking a 55 gallon tank are the tank inhabitants’ adult size, behavior, water parameter needs, and bioload. Careful planning is required to create a stable and healthy aquatic environment. This article provides quick answers about suitable fish for a 55 gallon aquarium, followed by in-depth information on recommended tankmates organized by fish type.
Quick Answers
- Freshwater fish like guppies, platies, mollies, danios, tetras, rasboras, barbs, corydoras and bristlenose plecos are suitable for a 55 gallon tank.
- Larger freshwater fish that can work in a 55 gallon include angelfish, gouramis, rainbowfish, some cichlids and larger catfish like pictus cats.
- For saltwater, smaller species of clownfish, gobies, blennies, chromis,Gramma species, damselfish, cardinals, basslets and firefish are appropriate.
- Some medium saltwater species like clowns, banggai cardinals, watchman gobies, blennies, damsels, dottybacks, hawkfish, wrasse and small angels can be housed.
- Avoid aggressive fish like oscars, arowana and large plecos that will outgrow a 55 gallon tank.
- Choose tankmates carefully and do not overstock the aquarium.
Recommended Freshwater Fish for a 55 Gallon Tank
Peaceful Community Fish
Some great options for peaceful community fish in a 55 gallon freshwater aquarium include:
Tetras: Most tetras stay under 2 inches and do well in groups in a larger aquarium. Good choices are neon, cardinal, rummynose, ember, black neon and glowlight tetras. Avoid fin nippers like bue-eyed tetras.
Rasboras: Many rasboras like harlequin, lambchop, glowlight and chili rasboras are perfect for community tanks. They are small, peaceful schooling fish.
Danios: Zebra danios are a hardy and active tiny fish that should be kept in schools. Giant danios grow larger but are peaceful.
Rainbowfish: Boesmani, threadfin and dwarf neon rainbowfish are relatively peaceful medium sized community fish.
Mollies: Sailfin, black, and Dalmatian mollies are livebearers that stay under 3-4 inches. Avoid mixing guppies and mollies though, as they can hybridize.
Platies: Varieties like mickey mouse,tuxedo,sunset and comet platies grow 2-3 inches and do well in community tanks.
Guppies are classic small bright community fish that should be kept in single sex groups unless breeding is desired. Fancy varieties produce vibrant colors.
Swordtails come in attractive varieties. Modest sized peaceful fish around 5 inches. Females tend to be less aggressive.
Hatchetfish are unique surface dwelling fish that stay under 2 inches. A group of 6 or more is recommended.
Pencilfish like neon dwarf pencilfish are shy but colorful schooling fish that stay under 2 inches. A peaceful tank is essential.
| Fish | Adult Size |
|---|---|
| Neon Tetra | 1.5 inches |
| Harlequin Rasbora | 2 inches |
| Zebra Danio | 2-3 inches |
| Boesmani Rainbowfish | 4-6 inches |
| Sailfin Molly | 3-4 inches |
| Sunset Platy | 2-3 inches |
| Fancy Guppy | 1-2 inches |
| Swordtail | 4-6 inches |
| Marble Hatchetfish | 2 inches |
| Neon Dwarf Pencilfish | 1.5 inches |
Centerpiece Fish
Some suitable centerpiece fish for a 55 gallon community tank include:
Gouramis: Pearl and honey gouramis are peaceful medium sized gouramis. Avoid aggressive three spot or giant gouramis.
Discus fish are challenging but make stunning centerpiece fish. Stick to smaller varieties like cobalt or turquoise discus in a 55 gallon. They require warm pristine water.
Angelfish are cichlid family fish that do well with small peaceful tank mates. Their elegant flowing fins add grace to the aquarium.
Dwarf cichlids like German blue rams are good 55 gallon choices. Avoid most African cichlids as they grow large and aggressive.
Giant danios grow to 4-6 inches but are active and peaceful. Their bold stripes stand out in contrast to small colored fish.
| Fish | Adult Size |
|---|---|
| Pearl Gourami | 4-6 inches |
| Turquoise Discus | 6-8 inches |
| Veiltail Angelfish | 6-8 inches |
| German Blue Ram | 3 inches |
| Giant Danio | 4-6 inches |
Bottom Dwellers
Some bottom dwelling fish suitable for a 55 gallon tank include:
Corydoras catfish are best kept in schools. Pygmy corys stay under 2 inches while peppered and albino cory reach 3-4 inches.
Bristlenose plecos only grow to around 5 inches and help clean algae off of surfaces. Avoid common pleco species.
Kuhli loaches are eel like bottom feeders that grow to 4-6 inches. They appreciate having hiding spots and being kept in groups.
Bichirs, like the ornate or albino varieties are other unique bottom dwellers. They can reach 12 inches so space is a consideration.
Synodontis catfish are another option. Some more manageable species are cuckoo, eupterus and nigriventris which stay under 5 inches.
| Fish | Adult Size |
|---|---|
| Pygmy Cory | 1-2 inches |
| Bristlenose Pleco | 4-6 inches |
| Kuhli Loach | 4-6 inches |
| Ornate Bichir | 8-12 inches |
| Cuckoo Synodontis | 4-5 inches |
Saltwater Fish for a 55 Gallon Reef Aquarium
Small Peaceful Fish
There are many options for small peaceful saltwater fish like:
Clownfish are classic reef safe clowns that do well singly or pairs. Percula, ocellaris, and skunk clown species stay under 3 inches.
Blennies like lawnmower, scooter, skunk blennies are bottom dwelling fish that reach 3-5 inches. They have great personality.
Gobies including clown, neon, firefish, watchman fish stay under 3 inches and are great reef tank choices.
Cardinalfish like banggai, pajama, blue-throated cardinals are shy but peaceful fish reaching around 3-4 inches in length.
Basslets (grammas) like royal, blackcap, coral beauty basslets are small and reef compatible. Several species stay under 3 inches.
Damselfish including 3 striped, electric blue, and lemon damsels are hardy small fish but can be territorial. Better in larger groups.
Chromis are schooling fish that do well kept in groups. Blue green, black, and bicolor chromis stay under 4 inches.
| Fish | Adult Size |
|---|---|
| Percula Clownfish | 3 inches |
| Skunk Blenny | 3-4 inches |
| Neon Goby | 2 inches |
| Bangai Cardinalfish | 3-4 inches |
| Royal Gramma | 3 inches |
| 3 Striped Damselfish | 4 inches |
| Blue Green Chromis | 3-4 inches |
Medium Reef Fish
Some medium sized reef fish suitable for a 55 gallon include:
Angelfish like the flame angel grow to around 5 inches and need peaceful tank mates. Avoid large angel species.
Butterflyfish – some smaller species like the spotted butterfly work well in larger reef tanks. They grow to around 5 inches.
Wrasse including cleaner, leopard, six-line wrasse are suitable smaller reef wrasses if provided plenty of rock work. They reach 4-6 inches.
Tangs should be chosen carefully based on adult size. Kole and bristletooth tangs stay under 5 inches. Avoid larger tangs.
Pseudochromis such as the firetail dottyback grow to around 3-4 inches but can be aggressive. Best kept singly.
Filefish are oddball fish but some species like the One Spot Foxface are smaller and can work in larger tanks. They reach around 5 inches.
Hawkfish like the flame hawkfish remain a more modest 4-5 inches, but require tanks with tight fitting lids.
| Fish | Adult Size |
|---|---|
| Flame Angel | 4-5 inches |
| Spotted Butterflyfish | 4-6 inches |
| Six Line Wrasse | 4-6 inches |
| Kole Tang | 4 inches |
| Firetail Dottyback | 3-4 inches |
| One Spot Foxface | 4-6 inches |
| Flame Hawkfish | 4-5 inches |
Tank Setup Considerations
To help create a healthy and stable aquarium environment in a 55 gallon tank, keep these tank setup guidelines in mind:
- Stock the aquarium slowly over time instead of all at once.
- Choose fish appropriate for the tank size. Avoid fish that grow over 12 inches.
- Select species that fit the tank inhabitants’ temperament, water parameters and space needs.
- For schooling fish, purchase groups of at least 6 fish.
- Include bottom dwellers like plecos and cory cats to help clean up and aerate the substrate.
- Incorporate enough hiding spots, caves and sight breaks to allow fish to establish territories and reduce aggression.
- Limit the number of territorial or aggressive fish in the aquarium.
- Use efficient filtration sized for at least twice the water volume.
- Perform partial water changes of 25-30% weekly to maintain clean water.
- Test water parameters regularly and address any issues promptly.
- Feed a high quality varied diet in moderation.
- Introduce tankmates carefully and observe their interactions.
- Have a plan in place to rehome any fish that don’t acclimate or grow too large.
Conclusion
A 55 gallon aquarium provides space to create an impressive freshwater community tank or mini saltwater reef environment. Take time stocking the tank and include fish appropriate for a 55 gallon system. Choose active schooling fish, striking centerpiece fish, and bottom dwelling clean up crews. Supplement with ample hiding spaces, rock work and efficient filtration. Work to maintain excellent water quality and compatibility between tankmates. With good planning and proper fish selection, a 55 gallon tank can produce a diverse, vibrant and healthy aquatic ecosystem.
