How Long Do Fish Live And Why?

by Editorial Staff | Updated on August 5th, 2022

The exact answer is 25 years.

Over the years, scientists have conducted studies on animals and humans to estimate their life spans and the elements that influence their life. Varied animals have different life lengths; genetic and environmental variables impact each animal’s life duration.

Fish are no exception; the species heavily influence the length of a fish’s life. In general, larger fish have a longer lifespan, whereas smaller fish have a shorter lifespan.

Fish in an aquarium live longer than fish in the wild. This article will look at the duration of a fish’s life and explain why they live so long.

How long can a fish live?

The longevity of a fish is affected by its species, and the two most common fish species are goldfish and bettas. Fish are classified into two types: those with a lengthy life span and those with a short life span.

Betas, killifish, swordtails, mollies, and platys have short life spans, but goldfish, loaches, silver dollars, pocus, and convict cichlids have extended life spans.

Fish that lay eggs are thought to live longer than fish that give birth to young.

Koi fish normally live for 25 to 30 years; however, some stories claim they may live for 200 years. Sharks are another fish species that may live indefinitely, with Greenland sharks being the longest-lived vertebrae.

Their average life expectancy is 272 years, with the oldest surviving for 292 years. On the other hand, these fish seldom reach their full potential due to various problems, the most important of which is poor care and the environment.

Average life expectations

Freshwater

In the wild, fish may live to be quite elderly. The Great Lakes Lake Sturgeon may live for 100 years, whereas Paddlefish can live for up to 55 years. Most freshwater gamefish appear to have a life span of around 7-9 years, with bigger predators surviving longer.

The oldest known age for bluegill is 10 years, and the oldest reported age for yellow perch is eleven years. Muskellunge have been known to live for up to 30 years, making them one of the longest-living freshwater predator fish. The northern pike has a life expectancy that is comparable.

The world’s greatest sportfish, the largemouth bass, may live up to 23 years but live just around eight years on average in northern lakes. Although its near cousin, the smallmouth bass, has lived to reach 26 years old, the normal lifetime remains 7-9 years.

Saltwater

The ocean is home to some of the world’s longest-living species, including the previously mentioned Greenland shark, which has an average lifespan of 272 years and was once caught with a 392-year-old specimen. This is more than twice the enormous and friendly whale shark’s 80-130 years.

Sailfish can live 13 to 15 years but generally only 5 years; the red drum can live up to 60 years, while fast-breeding mahi-mahi only lives 4 to 5 years. Unlike freshwater fish, saltwater fish’s size does not always translate into a longer lifetime.

How long do fish survive in their natural environments?

It’s hard to offer a single accurate statistic for life expectancy when you consider all the varied types of fresh and saltwater fish in all kinds of environments and temperatures. Sturgeons, for example, have lived to be over 100 years old, which is unusual even for their species.

A saltwater fish has a life expectancy of about 20 years. Freshwater fish often live to be approximately 15 years old. Another fascinating fact is that fish in cold water live longer than those in warm water.

The General Factors That Influence How Long Fish Live

A Fish’s Metabolism Can Affect Its Lifespan

According to research on the relationship between cell efficiency and how long fish live, the organism’s metabolism can estimate its longevity. As a result, the lifespan of a tiny fish may be less than that of a larger fish.

For example, the lifespan of a plecostomus fish or a clown loach is greater than that of a betta fish! However, it is critical to recognize that this is only one of many elements, and there are exceptions to the general norm.

The Environment Can influence the Average Lifespan of a Fish

While fish keepers have a notion of the average lifetime of domestic fish, this figure may be greatly extended or curtailed depending on the interior conditions of the aquarium or the pond.

Water quality, temperature, feeding cycles, maintenance, aeration, and the vulnerability of the fish tank dweller to illness can all impact how long aquarium fish survive.

To paraphrase the attitude, this explains why fish caretakers are so concerned about good fish tank cleaning and administration. It is advisable to create a timetable for all of your daily fish-keeping activities.

Once you’ve established a pattern, it’s important to stick to it to prevent stressing your fish. For example, regularity in fish feeding cycles and water changes helps maintain the ecosystem’s stability and health.

The aquarium’s water chemistry, as well as its nitrogen cycle, pH levels, and temperature, are non-negotiable aspects that must be maintained at ideal levels.

It is usually a good idea to keep a chart of these aquarium elements to keep track of any changes. Prevention is a great way to go if you want to increase a fish’s lifespan.

How Long Do Fish Live Is Influenced by Reproduction

Distinct fish species have different reproduction tactics, which directly impacts our topic of how long fish live.

According to the general view, fish that lay eggs have a longer life span, whereas fish that are live-bearing have a shorter life span. According to this idea, the average lifespan of a guppy fish, a live-bearing fish, is relatively short compared to the average longevity of a tetra fish, which lays eggs.

How to Maintain the Health of Your Fish

To maintain your fish healthy and happy throughout their lives, you must first understand fish needs in general. There are thousands of distinct fish breeds, and each one demands a unique level of care and nourishment.

It’s critical to remember that the health of your fish is a direct reflection of their surroundings. Keeping their tank clean will boost their health and prolong their lives.

How to Set Up Your Aquarium for Maximum Fish Health

Choosing the correct fish tank and aquarium equipment for your home or business is maybe the most crucial step in fish ownership. Ensure the aquarium is large enough for the fish you intend to purchase.

Bowls and tiny aquariums may appear to be a wonderful idea, but they are far more difficult to maintain and are frequently fatal.

If this is your first time keeping fish, unless you’re starting with a betta, consider purchasing an aquarium kit of at least 10 gallons that includes all the necessary equipment.

Remember that the fish you buy will likely not be full size, so make sure there is enough space for them to develop! Get the largest aquarium you can afford or fit in your space.

You’ll need an aquarium heater if you don’t live in a warm environment all year. Most tropical fish thrive at temperatures ranging from 75° to 80° F (goldfish prefer temperatures ranging from 68° to 74° F).

You should get a heater that is powerful enough to heat the amount of water in the aquarium to the required temperature based on the ambient room temperature.

Choose the Best Filter for Your Aquarium

Because fish pee in the same location, a good aquarium filter is necessary! Most filters now perform effectively in all three stages of filtration and are often rated for certain tank sizes.

Buying a somewhat oversized model is a good option if you want to maintain a bit messier fish, such as goldfish or cichlids, or fish that could have offspring or grow a lot larger.

If you have a drop-in filter, rinse it weekly and replace it monthly. If you have a canister filter, check the media regularly and clean or replace it as needed.

Natural Cover and Hiding Places Reduce Fish Stress

Some fish can swim in open water, but most require cover in the shape of plants, rocks, and other decorations to feel comfortable and choose a home.

If there isn’t enough structure in the tank, they may hide or be picked on, and stressed-out fish are more prone to get sick. When you first start populating your tank, add one or two new decorations every time you add a new fish, so the newbies have somewhere to go.

Investigate the Best Fish for Your Aquatic Environment

Always do your homework before purchasing fish to ensure that you have the required circumstances, the abilities to give good care and that they are compatible with any existing fish. When purchasing new fish, look for symptoms of stress or sickness and avoid fish that do not appear to be healthy.

Are they swimming unusually or huddling on the bottom? (except for catfish). Or are you hidden among the decorations? Keep an eye out for livebearers displaying clamped fins and shimmying.

Do they have ripped fins, bloodied patches, or little white specks on their fins or bodies like grains of salt? Are they exhaling quickly or gasping for air?

Most crucial, inquire how long they’ve been working at the shop. Never buy a fish that has just arrived; they are most likely anxious about their travel from the wholesaler, and relocating them will only worsen matters. Allow them to settle in for a week before purchasing.

Certain varieties of fish are schooling fish, which means they should be purchased in groups of at least six, ideally ten or more. Tetras, barbs, danios, rasboras, and corydoras catfish are examples. If your tank can’t hold so many fish, choose a different type of fish.

Some fish species are notorious for not getting along and should be kept separately. Redtail and rainbow sharks, Bettas, most knife fish, males of many cichlid species, and others are examples.

To Maintain Good Health, Acclimate New Fish Appropriately.

When you get your fish home, gently acclimatize them to your aquarium; don’t simply throw them in!

There are several approaches, but the general idea is to gently introduce new fish to your water to avoid overstressing them. Turn off the aquarium light and float the bag in your tank for half an hour, adding little quantities of tank water to the bag every few minutes before gently netting them into their new habitat.

Never let stored water into your aquarium; instead, trash it once you’ve released the fish. Allow them to settle down by turning off the aquarium light during the first few hours they’re in the tank.

Keep a watch on them for the first few days to ensure they’re eating, are not being tormented, and don’t exhibit any signs of sickness.

Finally, remember to switch out the light every night. Because fish can’t close their eyes to sleep, leaving the light on all the time stresses them out and fosters unwanted algae development.

If your light doesn’t have a built-in timer, acquire one from an aquarium or hardware shop and program it for 6 to 8 hours if you don’t have live plants and 10 to 12 hours.

To keep your fish healthy, perform partial water changes.

In nature, the water is either moving – as in rivers and streams – so waste is washed away, or the volume is considerably larger – as in ponds and lakes – so the trash is swept away.

Waste is soon diluted in both natural ecosystems. Regardless of your filter’s efficiency, waste by-products like nitrate can accumulate in an aquarium over time. (And, no, catfish, plecostomus, and other scavengers don’t get rid of it — they, too, defecate in the water!)

Water changes are the most important aspect of keeping a healthy, balanced aquarium. When you ask how much and how frequently you should execute them, you’ll hear varied replies, but 10% weekly or 25% bi-weekly is a reasonable rule of thumb.

At least once a month, attempt to vacuum dirt from the bottom, even if you have to go a bit deeper into the gravel. Remember that when water evaporates, all the nasty stuff stays behind, so repeatedly filling off your aquarium is not the same as changing the water.

Don’t overlook the significance of aquarium water upkeep! BEFORE you add new water to your aquarium, use an aquarium water conditioner to eliminate chlorine compounds and heavy metals.

Optimize your fish’s health by feeding them the right foods at the right times.

They say you are what you eat, which is true for fish too! Fish can be herbivores (vegetarians), carnivores (meat eaters), or omnivores (eat both plants and meat) (both).

Different fish require different nutrients, and while fish meals now are substantially superior to what was available in the “good old days,” you still need to know what your fish’s nutritional needs are and provide them with diversity. It’s ideal for keeping various fish food and treats on hand and cycling them into your fish’s diet.

Feed them only what they can finish in 2 minutes or less, and give them a day off once a week.

Feed once a day for the first 4 to 8 weeks after setting up your tank to reduce ammonia and nitrite buildup, then increase to twice a day if desired. Small, energetic fish require more frequent – but smaller – feedings than giant, slow-moving fish.

Editorial Staff

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