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Home > Fish > How to Choose the Right Pet Fish for You: 13 Expert Tips

How to Choose the Right Pet Fish for You: 13 Expert Tips

Plastic Aquarium Plants

Fish can be fun and interesting pets to keep, but there are a lot of important considerations before choosing a fish and bringing it home. Fish are often believed to have short lifespans, but in a number of cases, this is actually due to inexperienced or unprepared fish keepers not providing appropriate care.

This isn’t to say that people intentionally get fish to care for them improperly, but it does mean that many people don’t thoroughly consider all aspects of fishkeeping before bringing fish home. Here are the things you need to think about before you buy a fish.

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Top 13 Tips to Choose the Right Pet Fish

1. Freshwater or Saltwater

The most basic thing you should consider before even considering any type of fish is whether you’d like to keep a freshwater or saltwater tank. Both types of tanks have very different care requirements, but both do require routine care. They also both require at least a base working knowledge of caring for an aquarium to keep them successfully.

If you already have a particular fish in mind, then you’ll need to know what type of water it requires. Do thorough research because some freshwater and saltwater fish may look similar or have similar names. For example, there are both freshwater and saltwater angelfish, but they are not only not the same species, but they don’t belong to the same family.

saltwater coral reef aquarium at home
Image Credit: Vojce, Shutterstock

2. Tank Size

The size of your tank will really determine what types of fish you can have. While stunting due to an inadequate tank size can happen with some species, it doesn’t happen with all of them. On top of that, it’s not recommended to intentionally stunt the growth of your fish since it’s unknown how this impacts their internal organs.

If you have a set amount of space for a tank, then you may have to choose your fish based on the tank size your space can accommodate. If space is not an issue, it can open up the ability to purchase larger types of fish. Always check to see what the average maximum size of a fish species is before bringing it home. Many fish are sold at quite small sizes but grow to be far too large for most aquariums, like common Plecostomus and clown loaches.


3. Fish Size

Fish size and tank size don’t always relate to each other. You can never provide too much space, so, but you can provide too little. Consider how big of a fish you’re wanting to have. Some people like to have fish that are large and unique, often cutting an eye-catching look in a home aquarium, while other people prefer keeping shoals of nano fish.

Are you hoping to find a fish that will be well-suited to your pond? Fish that get large, like koi, are more likely to be visually enjoyable in a pond than stocking your pond with white cloud mountain minnows.

photo of a orange goldfish
Image Credit: Hannah jones, Unsplash

4. Tank Compatibility

Whether your tank will be freshwater or saltwater isn’t the only major water consideration you should have. You need to choose a fish that will be compatible with the type of tank you’re hoping to keep. Tropical tanks, for example, have warm temperatures, while blackwater tanks have low water pH, making them too acidic for some fish.

Water flow is also an important consideration since some fish cannot withstand strong water currents. Betta fish are a good example of fish that require very little water movement, while hillstream loaches love a tank with good water flow.


5. Tank Mate Compatibility

The tankmates you’re intending to keep together should help you determine what type of fish to get. Not all fish and invertebrates are compatible to be kept together, even if their water and tank requirements are identical. Some fish will eat anything they can fit in their mouths, including tank mates.

While goldfish make good pets, they are a good example of fish that will eat tankmates, and it’s not recommended to keep them with any tank mates they could eat, like small tetras and shrimps. This isn’t an aggressive behavior, but it is fish doing what they naturally do. It’s your job to consider the nature of each type of fish before choosing it for your tank.

fish in fish tank
Image Credit: Daniel Corneschi, Unsplash

6. Temperament

While some fish will eat their tank mates because of their natural predisposition to eating small live prey, other fish simply do not have the temperament that is suitable for community tanks. Cichlids are often looked to as an example of fish that aren’t generally good options for community tanks, although there are some exceptions to this, like German rams.

Some fish are territorial by nature, while others may bully when stressed or in an effort to protect territory. Shy fish are at the other end of the spectrum, but their temperament has a huge impact on their success in a tank with other fish. If they’re shy and fearful of their tankmates, then you may notice lots of hiding or not getting enough to eat.


7. Social Considerations

While it might sound silly to some, there are a large number of people who want a fish that will interact with them. Social and intelligent fish are far more likely to show visible attention to humans, especially when they see the person who feeds them.

Many fish are capable of recognizing patterns, faces, and routines, so you may notice a social fish begging at the glass at their dinner time every day. Some fish will even do things that might get your attention, like splashing water out of the tank or making noise within the tank.

Not all fish will have these types of interactions, though, and some fish are shy or nocturnal, so they may not interact or even make their presence known.

Goldfish swimming in the water
Image Credit: imso Gabriel, Pexels

8. Plant Considerations

Are you planning to set up an aquarium with live plants in it? You need to carefully choose the fish and plants you’re going to put in your tank if that’s the case. Plants are at risk of being eaten or uprooted by many species of fish, while others are likely to ignore the plants or use them for shelter.

Some species of fish will uproot plants in their attempts to root through the soil, which is common in goldfish and Geophagus cichlids. You may find creative ways to keep your plants safe, like using plant weights or planting them in terracotta pots instead of the soil, but this won’t work for all fish.


9. Cost

The cost of your tank setup and your fish should be considered when choosing a fish. The cost of fish can add up rapidly, especially if you’re buying multiple specimens of multiple species for a community tank.

Large tanks can be pricey, and that doesn’t even consider how much substrate you might need. Saltwater tanks are notoriously expensive to keep, even for small tanks. This is due to the specialized care and materials needed for these tanks, as well as the high price of many saltwater fish.

a beautiful planted tropical freshwater aquarium with fishes
Image Credit: S-F, Shutterstock

10. Number of Fish Needed

Not all fish are happy to live as a single fish in a tank, but some fish will only do well if they’re the only fish in the tank. Shoaling fish should always be kept in groups, with most requiring six fish to a shoal at a minimum but preferring 10 or more fish. Neon tetras and Otocinclus catfish are good examples of fish that are best kept in groups.

Some fish need to be kept in groups, but the numbers need to be specific to support healthy group interactions and prevent bullying, like tiger barbs. If the betta fish is what you’re after, then you’ll almost certainly have to keep a singular fish if you’re hoping for the flashy male betta. Female bettas can sometimes be kept in sororities, but they are less flashy than males.


11. Commitment

Just how much time are you willing to put into your aquarium every week or month? This is a huge consideration to take when choosing a fish, as well as the tank size and tankmates.

You should also consider the length of time you think you’re likely to be committed to your tank’s care. Some people know that they’ll be over having a fish tank in a year or two, while others want to make fish keeping a lifelong hobby.

Some fish live much longer lives than others, especially with appropriate care, so choose fish with an expected lifespan that you truly believe will match your interest in the tank.

aquarium glass cleaning
Image Credit: hedgehog94, Shutterstock

12. Domestic Bred vs. Wild Caught

It might come as a surprise to you to learn that not all fish you see in the pet store were bred to be there. A lot of fish come from the wild, and there are a few reasons for this. The most common reasons for this are that some fish are extremely difficult to breed in captivity, while others are relatively rare fish that are not kept in large enough numbers to establish a breeding program.

There can be environmental considerations for wild-caught fish but taking fish from the wild doesn’t always have a negative impact on the ecosystem. However, wild-caught fish are more likely to carry parasites and diseases than captive-bred fish that have been kept in proper conditions.


13. Legality

It might surprise you to learn that not all fish are legal to keep in all areas. Your state, city, or county may have restrictions on the types of fish you can keep. There are federal laws protecting a variety of endangered species, but it’s typically up to local and state jurisdictions to determine the fish that are either most likely to suffer from wild catching or the fish that are most likely to become invasive.

Red discus fish
Image Credit: LaMiranda, Pixabay

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It’s extremely common for people to not fully consider all of these things before bringing home a fish, but doing plenty of research and planning beforehand can ensure you are well prepared to bring your dream fish home.

The world of fishkeeping is fun and interesting, and there are more species becoming more widely available, making unique and exotic fish more attainable for everyone. Just make sure you’re ready for the commitment of providing care to your new fish for the length of their life.


Featured Image Credit: Huy Phan, Unsplash

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