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How To Choose A Pet Fish: The Essential Guide For Beginners

how to choose a pet fish
Pet fish are often the first pet a child learns to care for, but not all fish are created equally. Each has its required habitat, dietary needs, and socialization preferences, so choosing the right pet fish is never as simple as just walking into the local PetSmart and taking one home. Selecting the right fish involves a lot of research and a little bit of trial and error.

To choose a pet fish, think about how much time you have for regular cleanings, the most ethical pet stores nearby, what type of habitat the fish needs, and how to add new fish to an aquarium. Beginners tend to do well with easy-to-care-for fish, like Bettas, Goldfish, Guppies, and Mollies.

Throughout this article, you’ll learn the following about pet fish:

  • Benefits of owning fish
  • Time considerations
  • Fish to consider
  • Best places to purchase pet fish
  • Habitat considerations
  • Best aquariums for beginners
  • Nutritional needs
  • When and how to add new fish
  • Cleaning the aquarium
  • Things you can do to prevent fish from dying

Benefits of Owning Fish

The benefits of owning fish vary by age group. The aquarium is a decorative focal point and conversation starter for the family and guests alike for adults. The aquarium provides adults a place to relax at the end of the day for simple reflection or relaxation. It also offers a sounding board for those who like to talk to their pets.

As a parent, allowing children to have a fish as a first pet helps teach children responsibility without requiring a twenty-year commitment from you as a dog or cat would need. A fish’s life span is often 2-5 years, which is a fraction of other pets’ lifespan.

An added benefit to selecting fish as the first pet is that if the aquarium can sit in the child’s room, the soothing hum of the filtration system, the mesmerizing glow of the light, and the rhythmic motion of the fish are sure to help the most reluctant sleeper doze off.

Time Considerations

Most people consider owning pets and starting hobbies because they have some time to spare and desire to try something new. Although fish are the easiest pets to care for, they do require time and attention. So, before beginning, figure out how much time you have to devote to your new hobby. For example, consider that exotic fish take more time to care for than goldfish do, but both require some of your time.

Before choosing a pet fish, the best thing to do is give yourself a few weeks to research everything from the types of fish available to the differences between aquariums. Once you decide on the types of fish you want and the aquarium size the fish will need, you’ll be better able to determine how much time you’ll need to devote to your new hobby.

For the most part, caring for fish is much easier and less time-consuming than owning almost any other pet; however, the fish cannot care for themselves, so be sure that you have time to devote to the fish before making this investment.

Steps in Choosing a Pet Fish

The first step is to browse to see what you’re interested in. Walk into any pet store, and you’re bound to see colorful, vibrant, and exciting fish for sale. They’re mesmerizing to watch, and it’s easy to get caught up in which fish is the prettiest or the fastest.

It’s also easy to imagine that same aquarium set up in your home, which is why the first step is to browse so that you avoid selecting a pet fish on impulse. You must do your research after this browsing trip because if you go into the store without knowing what types of fish are suited for you, the journey is likely to end in frustration, or worse — a fish’s early demise.

After browsing the store’s stocked aquariums, here is how you can choose the best fish for yourself, your family, and the fish:

  1. Gain knowledge on the types of fish that make the best pets. Part of this fact-finding expedition should include what fish can live together and their typical lifespans and reproductive habits.
  2. Determine the best place to purchase your fish. Do your research first to avoid impulse buying. It would be best if you researched not only the fish but also where to buy them. Sometimes the leading chains are your best choice but don’t overlook private breeders. Each serves a unique purpose.
  3. Determine the best habitat for your fish. You know that fish live in water, but interestingly enough, not all fish can survive in all water types. The time you can devote to taking care of the fish will help you determine the best fish choice for you.
  4. Determine what supplies your fish will need. You know the fish needs food, but what kind is best? How much does it need? Does it need supplements or treats? How do you know when it’s hungry?
  5. Learn how to clean the fish’s habitat. Fish in aquariums don’t smell unless they have owners who don’t know how to take care of the tank. Don’t be that owner.

The Best Pet Fish for Beginners

how to choose a pet fish
There is a reason many doctor’s offices, dentists, and pediatricians have huge aquariums for patients to enjoy. Fish are mesmerizing and relaxing to watch. However, not all fish are created equally, nor should all fish live in the same tank. These tanks are also often cared for by professionals, so consider that before purchasing an enormous tank.

Here are the best fish for beginners:

Freshwater Fish

This variety is often easiest for the beginner. This list isn’t exhaustive but will help get you started without being overwhelming.

  • Betta: This species makes an incredible fish for beginners. It requires less space — if you only get one, a three-gallon (11.36-liter) tank like the Koller 3.5-Gallon Fish Tank will be sufficient. Bettas are also bright and quite active, mainly if you keep the water heated. Since they’re tropical fish, they like to live in water that is above 70°F (21.11°C).
  • Goldfish: This species is so close to first place that it really ties with the Betta. It’s also important to note that this fish, when cared for properly, can live up to twenty years. Like the Betta, Goldfish require less space than many other types. If you only have one, a twenty-gallon (75.71-liter) tank like the GloFish Aquarium Kit is sufficient.
  • Tetras: These fish come in various types and generally enjoy a five-gallon (18.93-liter) aquarium like a Tetra Crescent Aquarium Kit. One thing to consider with Tetras is that they like to live in a quiet area with moderate lighting. Tetras also get along with a lot of fish, so they make good companions.
  • Guppies: They’re the favorites of beginners and seasoned fish owners because they come in various colors and are relatively inexpensive. They enjoy a five-gallon (18.93-liter) take and get along well with other fish. A bonus is that although their lifespan is only two years, they’re livebearers, which means they give birth to live fish.
  • Mollie: They’re also livebearers but should probably be classified as intermediate fish owners because they can be sensitive to water conditions. Still, this trait also makes them good fish to learn from.

Saltwater Varieties

Beginners can most certainly purchase this variety, but there are additional habitat considerations to learn. They’re also more time-consuming; however, if time isn’t an issue, choosing between freshwater or saltwater fish can be an option for beginners.

  • Clownfish: This fish is easy to find, and it acclimates to changing water conditions quickly, making it a suitable beginner fish. It can do well in a 5-gallon (18.93-liter) tank if it’s the only fish in the tank. One suitable tank to consider is the Fluval Evo V Marine Aquarium Kit.
  • Butterfly Fish: This fish is easy to care for, and it does not need a large tank as long as it’s the only fish in the aquarium. Therefore, it’s suitable for beginners because they’re hardy fish that adapt to tank life quickly.
  • Pajama CardinalFish: This species is likely the easiest to care for of the saltwater varieties. They have no special requirements other than tank size. Although it gets along well with aquarium mates, it needs about 20 gallons (75.71 liters) of space to thrive.
  • Watchman Goby: This colorful, active fish is easy because it’s not prone to disease, and it gets along with other fish; however, mating males are aggressive, so only one mating pair should be in a single tank.
  • Chalk Bass: This species is also a hardy fish that isn’t prone to illness. They get along well with other fish but need at least a twenty-gallon (75.71-liter) tank. They will also need lots of hiding places in the tank to thrive.

It’s crucial to remember that freshwater and saltwater fish have vastly different needs, so they cannot live in the same environment; therefore, they cannot be combined in the same aquarium.

Best Places To Purchase Fish

Below are best places where you can get aquarium fish:

Local Pet Stores

Going to your local PetSmart or PetCo can be an incredibly satisfying experience if you go armed with a list of what you want and know the space you’ll have for your new hobby. The aquariums on display delight and provide opportunities to see how the fish interact with each other.

There are three main drawbacks to shopping at any fish store in person:

  • Although many first-time fish owners want to shop in person so that they can talk to an expert on fish, this expectation is often left unmet. The customer service staff is often highly trained in customer service but may know very little about fish or the many habitats required for them to survive. They may know little more than the name of the fish you ask to see and only because the name is printed on the aquarium.
  • The fish section can be overwhelming. The colors of the fish and the sheer number available can be daunting. It often becomes easy to go over budget, or worse, purchase more fish than you have room for once you get home.
  • The fish, though minimally cared for, are not cared for by an experienced aquarist. Typically, the sales staff in charge of the aquarium section of the store knows how to clean the aquarium and then feed live fish and remove dead ones.

Online Breeders

While purchasing fish in person provides immediate gratification, and you know what fish you’re getting and that it’s alive when you leave the store, there are several reasons to consider online breeders.

  • Breeders are experts in the types of fish they breed, and their livelihood depends on delivering healthy fish that can thrive in their new environment.
  • Online shopping is simply convenient, and breeders have perfected the process of shipping fish to aquarists.
  • Many online breeders offer guarantees. In fact, if there is no guarantee, there is another breeder online who offers one, so shop around.
  • Information is available in one place. The breeders want to sell their fish, but they also want the fish to have good homes so that the breeder might earn positive feedback and repeat customers. Therefore, they provide a wealth of information on topics from habitat to nutrition and health to help you choose the best companion fish for your specific interests.

Habitat Considerations

The first thing to remember about a fish’s habitat is that in ponds, rivers, and oceans, fish are stimulated by other fish of many colors, shapes, and sizes, and they need that stimulation. So, even if you think you only want one pet fish, purchase it as if it will never get a roommate, but it won’t be fighting for space if you did add other fish later. The more significant purchase will also be cheaper in the long run.

According to Fishkeeping World, there are 21 mistakes beginning fish owners make with their aquariums. That is a lot of room for error, but knowing a little bit about fish, in general, can help you avoid common mistakes.

  • Purchase the right size tank for the number of fish you want to care for. Don’t believe the myth that fish will grow to the size of the environment. That’s simply untrue.
  • Fish are small creatures, but they need a lot of space. However, this necessity has more to do with nitrogen cycles than actual space to swim. This cycle is rather complex but basically has to do with food and waste and how each gets broken down. The waste eventually turns into nitrogen compounds that can kill the fish, so the waste products must be offset with microorganisms.
  • The tank isn’t ready when water is added to it. It’s not even prepared when it has all of the rocks, plants, and the heater. The most important things to consider are the water’s temperature, harness, and pH balance. Test strips such as the Easytest Aquarium strips and a wide variety of thermometers are available for testing purposes.
  • Fish must acclimate to their new environment.
  • Fish need oxygen, so live plants are necessary for freshwater aquariums.
  • Fish may always appear hungry, but they’re not, so don’t overfeed them!
  • The water must remain fresh, and about 15% of it needs to be changed each week.
  • Many fish get along marvelously, but others have a predator/prey relationship, so shop with this in mind.
  • Get ahead of algae. First, make sure the aquarium isn’t placed in direct sunlight, and then clean algae at its first sign. If you don’t clean it immediately, it will grow and can then begin to cause the fish harm.
  • In ponds, rivers, and oceans, nature takes care of the habitat. An aquarium, however, must have a routine maintenance schedule of at least one cleaning and levels check per week.

Best Aquariums for Beginners

By far, the best place to start is with an aquarium kit. They seem more expensive at first, but after you add everything you need to a single aquarium purchase, usually the kit is the better deal. There are other things to consider before making the final decision on an aquarium.

  • Size. You absolutely must know how many and what kinds of fish you plan to keep before buying the aquarium. The tank’s size also determines how often it will need to be cleaned, so choose wisely.
  • Consider your budget. Once you know the size aquarium that will suit your needs, shop within your budget. However, you can’t just consider the initial cost because tanks must be maintained, and the larger the tank, the more maintenance it will require.
  • Determine your material. Aquariums come in glass and acrylic. The latter is more expensive but lighter and less likely to break, but acrylic does scratch more easily than glass, so this decision is a matter of preference.
  • Consider other aquarium needs. If you opt to purchase essentials separately rather than buying everything as a kit, make sure you have a filtration system, cover, and light. You’ll also need a heater, thermometer, plants, and other decorations for the fish to swim around. Further, don’t forget the gravel, cleaning tools, test strips, vacuum/siphon hose, and the water conditioner.

Nutrition Needs

To be so small, fish need a lot of ingredients to have a healthy, balanced diet. This article aims to make you aware that not all fish food is created equally, so it’s vital to read the food label to ensure the food has enough of what the fish needs and none of what it doesn’t.

Fish need the following:

  • Limited fat
  • Small amounts of fiber
  • Protein – depending on the species, fish will need between 15 and 50 percent protein.
  • Minerals – mainly calcium and phosphorus, but they also need trace amounts of others like iodine, iron, and zinc.
  • Vitamins – particularly Vitamins A and C

Fish don’t need the following:

  • Carbohydrates
  • An endless supply of food – Feed high-quality food that they will eat in about five minutes, twice per day. They don’t need to snack all day, and if they do, this action will create more waste, impacting the nitrogen cycle.
  • Pork, beef, or chicken scraps – If you do give them this food, make it a treat, as it can cause heart damage in large quantities. According to Hartz, this food should be clean and healthy and shouldn’t “introduce disease” into the tank.

When and How To Add New Fish?

Moving is stressful for all creatures, but fish may be the most affected by a habitat change. Being aware of this concern arms you with ways to add new fish to your aquarium in the safest way possible. Hartz reminds aquarists that some of the reasons fish die is because the water conditions will likely be vastly different from the pet store or breeder’s aquarium. Hence, it’s vital to acclimate your new pet to its new environment.

It’s equally important to prepare your current fish for a new arrival. Introduce new fish after feeding your current fish. This feeding will ensure that they won’t be aggressive towards their new mate. When they finish feeding, follow these instructions for a safe and less stressful entry for your fish:

  1. Turn off the aquarium lights so that the procedure is less stressful for the new fish.
  2. Keep the new fish in the plastic with its original aquarium water.
  3. Submerge the plastic in the top part of the aquarium for five or ten minutes
  4. Then add one cup of aquarium water to the plastic bag and continue to allow the new fish to swim in the bag submerged in the aquarium for another five minutes.
  5. Repeat step two until the bag is full.
  6. Once you’re ready to place the fish in the aquarium, do so with a net.
  7. Discard the water from the plastic bag into a drain. Adding it to the aquarium will change your water condition, creating a possible imbalance that may be stressful for the original fish.

Cleaning the Aquarium

Cleaning the fish’s habitat is so important and common that YouTube is filled with a variety of how-to videos that a simple Google search will reveal. Still, the importance of a clean aquarium cannot be overstated.

The most confusing part of cleaning the aquarium for beginners will be determining how often it’s necessary. Many experts say the tank needs cleaning once a week; others will say bi-monthly is sufficient. Some even say tanks only need a monthly cleaning. They all agree, though, the fish cannot survive in a dirty tank, and the fish cannot clean up after themselves.

Here is what you should consider:

  • What to do with the fish? You’ll leave the fish in the tank for most routine cleanings because you’ll never completely empty the tank. This method is easier on the fish, as catching them puts undue stress on them that can cause them to get sick.
  • Well-water and city-water are different. If you’re on city water, you’ll need a water conditioner for each cleaning to deal with chlorine. Well-water won’t need the conditioner, but you’ll need to check the pH balance and hardness more frequently.
  • Test the water quality. You want to have 0 ppm of ammonia and less than 40 ppm of nitrates.
  • Remove algae. This step will require a scraper. You don’t want to use soap or chemicals because they will kill the fish; just remove the algae with a scraper.
  • Care for live plants. Remove dead leaves and do any necessary trimming.
  • Remove some of the water. You don’t want to remove all of the water. The easiest way to remove the water is by using an aquarium siphon and vacuum, like the Aqueon Siphon Vacuum. This combination helps remove the water as well as debris.
  • Don’t forget about the filter. Change the filter at least once a month so that it won’t have the chance to clog and then overflow.
  • Refill the tank. Be careful to test the water temperature before putting it into the tank. The new water needs to be within two degrees of the original tank water.
  • Turn the equipment back on and wipe the class. Once the glass is clean, you have another two to four weeks of enjoyment before the cycle begins again.

How To Prevent Fish Death In Your Aquarium?

Sadly, the first death that many children deal with is the loss of a pet, and while it’s easier to hide a fish’s death from an unsuspecting child, it’s far easier to prevent the death in the first place.

Here are some things you can do:

  • Test the tank regularly. Nitrate and ammonia levels change periodically. In new tanks, they can change rapidly. Giving your tank time to achieve a proper balance before adding fish will create a healthier environment and reduce stress on the fish.
  • Change water slowly in small quantities. Also, wait about three days between each change. Make sure the tank stays at a constant temperature. The water should not fluctuate more than two degrees in either direction.
  • Don’t overfeed. Fish should be fed at the same time once every day. Provide only what they will eat in a five-minute feeding session, and then remove uneaten food.
  • Remove dead fish immediately. This step is important because dead fish will rot quickly, polluting the water and making it dangerous for the other fish.


Owning a fish is a rewarding experience, and fish are relatively easy to care for. When considering if this hobby is a good fit for you, consider the time you have to put into the hobby, the equipment you’ll need, and the needs of the fish. Chances are, though, if you’re researching, you’re ready to begin this adventure and will enjoy many years as an aquarist.