How Long Do Fish Live in a Tank? A Species-by-Species Guide

The short answer

It depends on the species, and sources measure different things. Aqueon, an aquarium maker, gives bettas an average of 3 to 4 years and properly cared-for goldfish “can live over 20 years in captivity”. Livebearers differ: Aqueon says most live 5 to 7 years; Aquarium Co-Op, a retailer, gives fancy guppies 2 to 3 at 76 to 78°F.

Each row below names its source and what its figure measures: an average, an upper limit, a database record or one owner’s claim. This guide covers freshwater fish only.

Aquarium Fish Lifespans by Species

FishBase is a scientific fish database and AnAge an animal ageing and longevity database. Practical Fishkeeping (PFK), a fishkeeping magazine, lists ages “as claimed by their owners”.

Fish	Source: what it gives	Figure
Betta	Aqueon: “average lifespan”	3–4 years
Betta	Tree of Life (vet clinic): “on average”, “With proper care”	3–5 years, “sometimes longer”
Betta	FishBase: “max. reported age” (a maximum)	2.00 years
Goldfish	Aqueon care guide: “can live”, “When properly cared for”, “in captivity”	over 20 years
Comet goldfish	Aqueon blog, citing Dr. Jessie Sanders of Aquatic Veterinary Services: “often”; “some”	into their 20s; into their 30s and 40s
Fancy goldfish	Aqueon blog: bought from “a respected goldfish breeder or aquatics pet retailer”; “Lower-quality”	into their 20s; about 10–15 years
Goldfish	FishBase: “max. reported age”; its age table: “in captivity”; a river sample in China	41 years; 30 years; 17 years
Goldfish	AnAge: maximum, labelled “wild”	41 years
Goldfish	PFK: one owner’s claim	43 years
Fancy guppy	Co-Op: average at 76–78°F (“should”); at 82°F; at 72°F (“may”)	2–3 years; 18 months; 3.5 years or longer
Guppy	PFK: average of owners’ reports, leaving out one 9-year claim	18 months
Platy	Co-Op: “Healthy platies can live up to”, in “optimal environments”	3–4 years
Livebearers	Aqueon: “Most livebearers” (mollies, platies, swordtails, guppies)	5–7 years
Zebra danio	AnAge: “Outbred zebrafish”, “captivity”: mean; maximum	3.5 years; 5.5 years
Neon tetra	PFK: one owner’s claim	10 years
Bronze cory	PFK: one owner’s claim	11 years
Angelfish	Co-Op: “up to”, given “a clean environment with minimal stress and high-quality foods”	8–12 years
Angelfish	PFK: one owner’s claim	6 years
Common pleco	PFK: “Lots of ‘common plecs'” (its list names Liposarcus pardalis)	27–28 years
Dwarf gourami	Co-Op: “With good care and diet”, “about”	2–4 years
German blue ram	Co-Op: “up to”, given “high-quality foods and clean water at the right temperature”, which it puts “ideally between 84-86°F”	4 years

Co-Op alone gives the platy, dwarf gourami and ram figures here, and AnAge alone the zebra danio’s. Only PFK gives neon, cory and pleco ages; its neon, cory, angelfish and goldfish entries are single owners’ claims, and for plecs it says “Lots” were at 27 or 28. PFK puts “big questions marks” around a nine-year-old guppy and a 12-year-old white cloud minnow on its list.

Aqueon’s betta average (3 to 4 years) and Tree of Life’s (3 to 5) differ. FishBase’s 2.00-year “max. reported age”, from a North American fish mapping database, is a different measure (a maximum record) and is lower than both averages; FishBase does not say whether that fish was wild or kept.

For goldfish, FishBase’s summary gives 41 years and says “They last long in captivity”; its own age table lists 41 for Asia, 30 “in captivity” and 17 from China’s Dongjiang River. AnAge labels its 41-year record “wild” and says: “While known for their often short lifespan when kept as pets, goldfish can have long lifespans, possibly exceeding 40 years.”

For livebearers the sources differ. Aqueon’s 5 to 7 years is for most livebearers, a group its guide says includes platies and guppies, while Co-Op gives platies “up to” 3-4 years and fancy guppies 2 to 3, and PFK’s readers’ guppy average is 18 months. PFK’s owner list has a swordtail and a sailfin molly at 5 years. No source here reconciles them.

Co-Op also says ram cichlids “have the reputation for being less hardy compared to other species”, and that it occasionally gets dwarf gourami batches “that have genetic deformities caused by overbreeding”.

How to Read These Figures

Name the fish exactly

Aqueon gives comets and fancy goldfish different figures, and Co-Op says “these new lines of fancy guppies are not as resilient as the original species found in the wild.” Our guide to aquarium fish for beginners covers ten commonly kept species.

Allow for age at purchase

Our reading of PFK’s note on its list: “Note that some of the fish listed are still alive and well, and many would have been over a year old when purchased.” Our guides to adding new fish to an aquarium and why to acclimate new fish slowly cover acclimation.

Watch older fish closely

Our advice, from PFK’s summary of what fish health expert Dr Peter Burgess told it: “It seems that old fish are at greater risk of certain diseases and are also less able to withstand unsuitable water conditions or bullying.” If any fish looks unwell, test the water and contact an aquatic veterinarian.

What Affects How Long Fish Live

Of the lines below, only PFK’s, Aqueon’s goldfish blog and Co-Op’s guppy figures tie care to lifespan in so many words (Co-Op’s table figures also carry care conditions). The rest is a maker’s and a vet clinic’s care advice that gives no lifespan; linking it to lifespan is our reading.

Water quality

PFK says “No fish will last very long in poor water conditions, if fed a diet that is poor in nutrients, or if kept in a stressful situation.” Aqueon says “The only safe ammonia level is zero.” and “The only safe nitrite level is zero.” Of nitrate, it says “Nitrates are not toxic to fish per se, however, long term exposure to high levels can stress them, stunt growth, damage organs and make them more susceptible to disease.” It adds that “Nitrate toxicity to fish varies depending on species, age and overall health, but levels above 50 ppm are undesirable in freshwater aquaria”, and that “Regular partial water changes, proper filtration, sensible stocking and feeding habits as well as the use of live plants will help keep nitrates in check.”

Our guide to changing fish tank water covers how much and how often. Aqueon says to “Always treat tap water with a water conditioner to neutralize chlorine and ammonia before adding it to the aquarium”; our water conditioner roundup compares eight.

Our freshwater test kit roundup suggests starting “with the API Freshwater Master Test Kit for ammonia, nitrite, nitrate and pH”, and notes it has “No GH, KH, chlorine or phosphate test, so hardness needs a second kit”.

#	Preview	Product	Price	Link
1		API Freshwater Master Test Kit 800-Test Freshwater Aquarium…Liquid master kit	$35.98 Prime	Check on Amazon

Prices as of Nov 10, 21:05 UTC

Tank size

Aqueon: “Goldfish should never be kept in bowls, small aquariums or any unfiltered container! In addition to having relatively high oxygen demands, they grow to be quite large and generate a significant amount of waste, which can be harmful if allowed to accumulate.” Its goldfish blog says “A goldfish’s longevity depends on a healthy pedigree, its aquarium quality, and how you care for the pet.” Our guide to fish for a 10-gallon tank gives each source’s tank figure for goldfish.

Tree of Life says “While often marketed as low-maintenance pets that can live in small bowls, bettas thrive when provided with proper tank size, warm water, filtration, and enrichment.”

Temperature

Aqueon says “When it’s too cold, they’re less active, their appetite is reduced and their immune systems are compromised, making them more susceptible to disease.” It adds: “When it’s too warm, their metabolisms and breathing speed up, and they use more oxygen. The problem is, as water warms up it holds less oxygen, which further stresses the fish.” It says to “choose fish whose preferred temperature ranges match the temperature of your tank”: “Tropical fish, for example, do best between 75° and 80°F”, while goldfish and other cold-water species “prefer temperatures below 70°F”.

Co-Op recommends a heater “to keep the water warmer at 76 to 78°F” for fancy guppies; at 82°F they “grow faster and make more babies”, and at 72°F “they’ll take forever to reach adulthood and may only have babies every six months.” Only Co-Op gives lifespans by temperature here, and only for fancy guppies. Aqueon’s livebearer guide says “Most livebearers do best between 74° and 78° F” and advises a heater if the room is below 74° F. Our guide to what temperature a fish tank should be gives ranges by fish type.

Ready to buy?

Our freshwater test kit roundup compares nine kits, and our Tank Setup & Care section has more guides.

Frequently Asked Questions

Q. What pet fish has the shortest lifespan?

Of the figures in this guide, the shortest are 18 months: Co-Op’s for fancy guppies kept at 82°F (it recommends 76 to 78°F), and PFK’s average for its readers’ guppies.

Q. Which fish lives the longest as a pet?

Among the fish in the table, the goldfish: FishBase’s age table gives 30 years “in captivity”, and PFK’s owner list includes a 43-year-old goldfish.

Q. How long do small tropical fish live in a tank?

PFK’s writer says “Most tetras, rasboras and small barbs can hit five years old, as you might expect”, and that its reader survey found some at “seven, eight and even 10 ten years of age” (its wording). These are what some fish reached, not averages; PFK’s own guppy average is 18 months.

Q. What kills fish in a tank?

Our guide to why fish die in an aquarium covers the water causes to check first. If fish are sick or dying now, test the water and contact an aquatic veterinarian.

Sources (20)

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Aquarium Tales Team

Written and reviewed by the Aquarium Tales Team. See the About page for how we work.