How Long Do Aquarium Fish Live? Lifespan, Size and Tank Data for 29 Species

What are the main findings?

The findings below come from AquaCompat's species traits dataset, which covers 29 species and was checked against its published sources in October 2026.

• The Bristlenose Pleco has the longest reported lifespan of the 29 species, 25 years, a longevity record listed by Practical Fishkeeping rather than a typical age.
• Goldfish are reported to live 6–20 years and oscars 10–20 years, the widest ranges among the 14 species with both ends of a lifespan published.
• Cherry shrimp, crystal red shrimp, mystery snails and nerite snails have the shortest reported lifespans in the dataset, about 1–2 years.
• FishBase reports betta fish living up to 2 years, the lowest figure for any fish in the dataset.
• The oscar is the largest species covered, at 14 in (35.6 cm), and the chili and galaxy rasboras the smallest, at 0.8 in (2 cm); the oscar also needs the biggest minimum tank, 75 US gal (284 L).
• Small size does not mean a short life: Practical Fishkeeping's owner-reported records list the neon tetra, which reaches 1.2 in (3 cm), at up to 10 years.
• 7 of 29 species, including the molly and three Lake Malawi cichlids, have no lifespan that AquaCompat could trace to a published source.

How long do common aquarium fish live?

Most common aquarium species live two to five years, a smaller group of catfish, cichlids, loaches and goldfish is reported at 10 years or more, and cherry shrimp, crystal red shrimp, mystery snails and nerite snails are given one to two years, based on the 22 species in AquaCompat's dataset with a sourced lifespan. The chart shows the upper end of each range: what a species can reach, not an average.

Which aquarium fish live the longest?

The longest-lived species in the dataset are the bristlenose pleco, goldfish, oscar and kuhli loach, each with a published figure of 17 years or more. The oscar's 10–20 years is a typical range given by both Seriously Fish and Aquarium Co-Op. The goldfish range combines OATA's six to eight years, which it says can pass 20 with good water, and fishkeeping.co.uk's estimate of about 20 years for single-tailed goldfish. The figures for the bristlenose pleco and the kuhli loach (up to 17 years) come from Practical Fishkeeping's table of owner-reported records.

These species are a decade-long plan, which is why the oscar tank-mate list and the goldfish tank mates guide are built around adult fish. Angelfish (8–12 years, per Aquarium Co-Op) and corydoras (a bronze corydoras recorded at 11 years, per Practical Fishkeeping) sit just below; see the angelfish compatibility list and the corydoras tank-mate guide.

Which aquarium animals have the shortest lives?

Dwarf shrimp and small snails have the shortest lives in the dataset. Shrimp Science and Shrimp and Snail Breeder give cherry shrimp and crystal red shrimp 1–2 years, and Aquarium Co-Op gives the mystery snail 1–2 years. A breeding colony of cherry shrimp and their tank mates replaces itself, so steady water matters more than the age of any one shrimp. Among snails only the assassin snail, at up to 5 years, is a longer-term addition to a snail-friendly community.

Among fish, the betta has the shortest sourced figure: FishBase reports Betta splendens living up to 2 years as a maximum, and it is the only betta lifespan source in AquaCompat's file, so it should be read as one reference value.

Which aquarium fish grow the biggest?

The oscar grows the biggest of the 29 species, reaching 14 in (35.6 cm), followed by the goldfish at 10 in (25.4 cm) and the angelfish at 6 in (15.2 cm), according to AquaCompat's dataset. Apart from those three, the discus, the kenyi and peacock cichlids, the bristlenose pleco and the molly, every species stays under four inches.

Why do size figures for the same fish disagree?

Size figures disagree mainly because sources measure different things. Seriously Fish usually quotes standard length (SL), which leaves out the tail fin, while FishBase often quotes the largest total length (TL) recorded, tail included. For the oscar, Seriously Fish gives 350 mm SL, Aquarium Co-Op 10 to 12 inches or more, and FishBase a maximum of 45.7 cm TL with a common length of 24 cm; AquaCompat's 14 in (35.6 cm) follows Seriously Fish. For goldfish, OATA gives about 25 cm in aquaria and FishBase a maximum of 48 cm TL. Height matters too: Aquarium Co-Op describes angelfish as 6 inches long but 8 inches tall including fins.

Adult size also drives compatibility. Seriously Fish and Maidenhead Aquatics say the angelfish eats neon-sized tetras, and Maidenhead says discus tank mates must not be small enough for an adult discus to swallow, a rule reflected in the discus tank-mate rankings. The species compatibility checker compares adult sizes, not shop sizes, for the same reason.

How big a tank does each species need?

Minimum tank sizes in the dataset run from 5 US gal (19 L) for cherry shrimp and single snails to 75 US gal (284 L) for one oscar. Most small schooling fish land between 10 and 20 US gallons, and the cichlids need 40 gallons or more. The table gives the basis for each figure.

What does a minimum tank size actually cover?

A minimum tank size covers the smallest group the source had in mind, not a full community. Seriously Fish usually gives a base footprint, such as 60 by 30 cm for the neon tetra, which AquaCompat converts at 30 cm depth and rounds up to 15 US gal (57 L). Aquarium Co-Op's 75 gallons for the oscar is for one fish, rising to 90 to 100 gallons for two.

Goldfish have the widest spread. The 48 US gal (182 L) figure is fishkeeping.co.uk's recommendation for one single-tailed goldfish, plus about 12 US gallons per extra fish; fancy goldfish are given 20 to 37 US gallons depending on the source, and OATA gives 100 litres for any adult goldfish. For bettas, Aquarium Co-Op says 5 to 10 gallons minimum and recommends 10, the figure used here.

Mixed tanks need more than the largest single minimum. The aquarium stocking calculator checks a planned group against a chosen tank, and the tank setups by size show which species fit a given volume, such as the 10-gallon community tank and the 20-gallon planted tank.

Which species have no sourced lifespan?

Of the species on this page, 7 of 29 species have no lifespan figure that AquaCompat could trace to a published source, so they are left blank rather than filled with an estimate. Their size and tank figures are sourced and appear in the tables above.

• Molly, a hybrid-rich livebearer group (see the molly care guide)
• Endler's livebearer (see the Endler's livebearer profile)
• Kenyi cichlid
• Peacock cichlid
• Yellow lab
• Chili rasbora
• Galaxy rasbora

The three Lake Malawi cichlids share one page of African cichlid tank mates. A sourced lifespan will be added to the dataset when one is found.

Why do published lifespans for the same fish vary so much?

Published lifespans vary because sources report different things: typical captive ages, single record fish, wild ages and ages at a particular water temperature.

• Records versus typical ages. Practical Fishkeeping's longevity table lists the oldest fish its readers reported, including the harlequin rasbora (up to 6 years). These are upper limits, not what most owners should expect.
• Wild versus captive. Practical Fishkeeping says cardinal tetras live about a year in the wild but up to five years in captivity.
• Average versus oldest. FishBase gives domesticated zebrafish an average of 3.5 years and an oldest of about 5.5 years.
• Temperature. Aquarium Co-Op says guppies live 2 to 3 years at 76 to 78 °F (24 to 26 °C) but about 18 months at 82 °F (28 °C). Applesnail.net gives mystery snails 12 to 16 months at 25 °C (77 °F), longer when cooler.
• Variety. Fishkeeping.co.uk puts single-tailed goldfish at about 20 years and fancy goldfish at about 12.

A common belief is that small fish are short-lived and big fish long-lived. The data do not support it as a rule: the neon tetra, at 1.2 in (3 cm), has an owner-reported record of 10 years, while captive discus typically live 3–5 years, exceptionally longer, according to a 2008 Neotropical Ichthyology paper by Crampton. Keeping water within each species' range, as set out in the aquarium temperature guide, matters more than body size.

What do lifespan and adult size mean when you buy a fish?

A juvenile oscar can grow to 14 in (35.6 cm) and live 10–20 years, a commitment to a 75 US gal (284 L) tank for over a decade. The bristlenose pleco is a gentler case: a long record age, but a modest 5 in (12.7 cm) and a 20 US gal (76 L) minimum.

Short-lived species carry a different commitment, about breeding and replacement rather than decades. Aquarium Co-Op notes that female guppies give birth about every 30 days, and the guppy community guide covers tank mates for a growing livebearer group; the best betta companions page covers the betta's shorter horizon.

Three checks are worth making before buying.

1. Look up the adult size, not the shop size, of every species planned.
2. Check each species' minimum tank, then run the whole group through the stocking calculator.
3. Plan for the upper end of the lifespan range: a long-lived species needs a tank you expect to keep running that long.

Full care data for each animal is in the species directory.

How we built this data

AquaCompat keeps one fact file for each of the 29 species on the site. Each value in a fact file was copied from a named published source (mainly Seriously Fish, FishBase, Aquarium Co-Op, Practical Fishkeeping, Shrimp Science and OATA), with a short evidence note on what the source says. Sources were checked in October 2026. The tables on this page are exported directly from those files; no value was added for this page.

Definitions used:

• Lifespan is the minimum and maximum years a source gives. Where a source gives only a maximum or a record age, the minimum is blank.
• Adult size is a representative maximum adult length in inches, usually Seriously Fish's standard length.
• Minimum tank is the smallest tank a source recommends, converted to US gallons. Footprints are converted at the stated depth, or 30 cm when none is given, and rounded up.

AquaCompat's own calculations are limited to unit conversions and sorting. The data have clear limits.

• Most lifespan figures are expert estimates or owner reports rather than measured studies of aquarium fish.
• Several maxima are single records and overstate what most fish reach.
• Group names such as corydoras, molly and nerite snail cover several species; values follow a named reference species.
• The 29 species are popular freshwater species, not a random sample of the hobby.

The wider approach to sources and scoring is set out on the AquaCompat methodology page.

How to cite this page

Use this citation, or link to the page with the figure you use.

AquaCompat, "How Long Do Aquarium Fish Live? Lifespan, Size and Tank Data for 29 Species", updated 22 October 2026, https://aquacompat.com/data/aquarium-fish-lifespan-and-size/.

The data, tables and charts on this page are free to reuse under a Creative Commons Attribution 4.0 (CC BY 4.0) licence, provided you credit AquaCompat with a link to this page. Please also name the original source shown in each figure's evidence note.