Anyone who is thinking about buying killifish for an aquarium will have a lot to consider. There are so many types of killifish out there that you can purchase.
There are hundreds of these fish, and it wouldn’t be possible to cover them all. However, it’s certainly possible to go over the most well-known and popular types.
Read on to learn about various types of killifish. This will give you a bit of information about the fish so you can decide if they’re right for you.
After reading all of the information, it should be easier to figure out which fish appeal to you. Anyone who is looking into killifish options will benefit from learning more about them.
Can Killifish Live in Freshwater?
Yes, it’s well known that killifish mostly live in freshwater. Typically, you’ll find killifish living in tropical and subtropical bodies of water.
You’ll mostly find them living in freshwater lakes, streams, and rivers. There are many different types of killifish out there that live in freshwater.
Below, you’ll learn about common types of freshwater killifish that people keep in home aquariums. These are the fish that you’ll most likely be focused on buying at first.
Freshwater Killifish
There are many freshwater killifish that are worth considering. Caring for these fish is pretty simple most of the time.
Getting some freshwater killifish for your fish tank will be a good idea if you’re a beginner. They can also be a lot of fun for experienced aquarium enthusiasts.
Golden Wonder Killifish
Golden wonder killifish might be the most well-known killifish overall. They’re semi-aggressive fish that can adapt to living in community tank settings.
You simply need to be careful to pick tank mates that are large enough to deal with them. These fish grow to be approximately 3.9 inches at maturity.
You should keep them in 20-gallon fish tanks so they can thrive. Overall, these fish are easy to care for, but you do need to maintain the tank properly.
Feed this fish a healthy diet, and it can live for up to four years in your aquarium. It should be a very good fish to own for most people.
Bluefin Notho Killifish
Bluefin notho killifish grow to be two and a half inches long. They have blue and orange bodies that stand out in a nice way.
These are peaceful fish that you don’t have to worry about too much. They’re easy to care for, and they can be put in community aquariums.
You should keep these fish in 10-gallon fish tanks or something larger. They’ll be good fish for anyone who is new to this hobby.
Redtail Notho Killifish
Redtail notho killifish are incredibly popular. They’re great to own because they’re so easy to care for.
Many people recommend these fish to those who are looking to get into caring for killifish. They’re small and only grow to be two and a half inches long.
You can keep them in 10-gallon fish tanks comfortably. They live between one and two years in fish tanks when you care for them well.
They’re fairly peaceful fish that should work well as community tank fish. This is one of the best fish to consider for most people.
Blue Gularis Killifish
Blue gularis fish can be kept in community tanks, but many people don’t bother. They’re semi-aggressive fish that can bother tank mates that are living in the bottom and middle sections of the tank.
They grow to be between three and a half and five inches long at maturity. This makes them fairly large as far as killifish go.
You’ll find that blue gularis are fish that look very pretty. Their bodies have varied bright colors, and you’ll love the way their delicate fins look.
They can add a certain wow factor to your fish tank if you choose to buy them. Since they’re temperamental fish, it’s best to buy these only if you have some experience under your belt.
American Flagfish
American flagfish are some of the most interesting killifish that you will find. These fish have a pattern that sort of looks like an American flag, and that’s why they’re called American flagfish.
Since they’re bright and colorful fish, many people are drawn to them. They grow to be 2.6 inches long, and they should be kept in 15-gallon aquariums.
These fish aren’t very peaceful, though. They’re semi-aggressive and might bother some tank mates.
Note that American flagfish are omnivorous. They might choose to nibble on plants in the aquarium from time to time.
Kisaki Killifish
Kisaki killifish are peaceful fish that grow to be two and a half inches long. You should buy a 10-gallon tank for these fish to keep them comfortable.
These are fish that stand out well in a fish tank. They have bright red and orange bodies with beautiful blue eyes.
It’s also nice that they’re among the peaceful types of killifish. Males do fight a bit over females, but other than that, they’re easy fish to deal with.
You shouldn’t have a problem keeping these fish in a community aquarium so long as you research compatible tank mates. Kisaki killifish will live for one to two years in a fish tank with optimal care.
Argentine Pearlfish
Argentine pearlfish are semi-aggressive fish that might not make great community tank fish. Most people choose to keep them in tanks with just their own kind.
You shouldn’t keep more than one male in the tank. The males tend to fight a lot, but one male and four or five females will work out fine.
They grow to be 2.75 inches long and should be kept in 15-gallon aquariums. These fish don’t live for a long time.
Expect Argentine pearlfish to live for up to eight months in your fish tank. Some people shy away from the short-lived killifish options.
Blackfin Pearlfish
Blackfin pearlfish do have some similarities when compared to the Argentine pearlfish mentioned above. They also grow to be 2.75 inches long, and they’re expected to live for around eight months, too.
The big difference between the two types of fish involves the fins. Blackfin pearlfish have larger dorsal and anal fins than Argentine pearlfish.
Also, these fish have speckles that line up in such a way that they appear to form vertical lines. These are pretty fish that are worth looking into.
A blackfin pearlfish can be kept in a 15-gallon aquarium without a problem. As with the Argentine pearlfish, be careful not to keep more than one male in the tank, or you’ll have problems with fighting.
Daisy’s Ricefish
Daisy’s ricefish are pretty despite not standing out too much overall. These fish are fairly tiny since they only grow to be around one inch long in adulthood.
It’s best to keep them in a 10-gallon tank. If you plan to keep more than three or so of them, it’d be better to go with a larger aquarium just to give them more space.
These are peaceful schooling fish that won’t be tough to take care of. They’re omnivorous, and they need to be fed high-quality meaty foods as well as veggie-based foods.
Since they’re extremely hardy fish, they’ll be good choices for most people. You don’t need a huge tank to enjoy them, and they’re nice fish to own.
Two Stripe Lyretail
The two stripe lyretail is a stellar option for someone who isn’t used to taking care of fish. These fish are decidedly easy to keep, even if you’re a total beginner.
They’re peaceful fish as well, and that helps. You won’t have to deal with problems in the fish tank as often since these fish will mind their own business.
At maturity, two stripe lyretails will wind up growing to be two inches long. They should be very comfortable in 10-gallon aquariums.
Since they’re bright and cheerful-looking fish, it’s easy to recommend them. Even if you just want a pretty fish for a community tank, it’ll be great to buy some of these.
Blue Lyretail
Blue lyretail killifish are truly stunning to behold. The males are especially colorful, but all of these fish have lyre-shaped yellow tails.
They grow to be two and a half inches long at maturity. You’ll have a good experience if you keep these fish in 10-gallon aquariums.
On average, blue lyretail killifish will live for three years. They can be a bit on the aggressive side as far as killifish go.
They’re only semi-aggressive, but you’ll need to pick tank mates carefully if you choose to put them in a community aquarium. Even so, they’re pretty fish that can be so much fun to own.
Chocolate Lyretail
The chocolate lyretail is worth buying if you want a colorful fish. These fish have orange and light brown bodies that feature little red dots.
Since they’re so colorful, they’ll easily add a bit of charm to your tank. They’re fish that grow to be between two and three inches long.
You should keep chocolate lyrefish in 10-gallon fish tanks. It won’t be hard to care for them since they’re not picky fish.
It’s also nice to know that these fish are generally peaceful. They’re fine options when looking for killifish to put in a community tank.
Magnificus Killifish
Magnificus killifish are some of the prettiest fish that you can buy. They have a rainbow coloration that allows them to show off many bright colors.
These are small fish that only grow to be around one inch long. They live for approximately two years when you care for them properly.
Since they aren’t big, you can keep them in 5-gallon fish tanks or 10-gallon fish tanks. They’re rather easy to care for as well, and this makes them good choices for newcomers to the hobby.
Magnificus killifish will add a lot of color to your aquarium. They appreciate it when you put floating plants in the tank as decorations.
Red-Striped Killifish
Red-striped killifish are another option that you’ll want to consider. You can buy these fish in several different colors.
They can have red bodies, orange, or blue bodies. You’ll see red spots and horizontal stripes on their bodies as well.
These fish grow to be up to two inches long. You should keep them in a 10-gallon fish tank to get the best results.
When you’re looking for peaceful killifish, it’s good to buy these ones. They’re rather peaceful and work out well in community tanks.
Clown Killifish
Clown killifish are incredibly popular. They’re well-loved by many people because they’re easy to take care of, and they’re rather peaceful for killifish.
You can keep these fish in fairly small fish tanks. It’s common for people to keep them in 5-gallon tanks or 10-gallon tanks since they aren’t very big.
A clown killifish will usually grow to be no larger than 1.4 inches. They can live for up to five years, too, so they’re fairly long-lived for killifish.
So long as you take care of the basic needs of these fish, it won’t be hard to keep them happy. These are good choices for people who are buying killifish for the first time.
Volcano Killifish
The volcano killifish will grow to be two inches long once it reaches adulthood. This is a very cute carnivorous fish that loves to eat insects.
Since they’re not overly big fish, they’ll do fine in a 10-gallon fish tank. These pretty fish have long bodies that are most commonly a violet-brown color.
They also have bright yellow or gold flanks. Sometimes you’ll notice red spots on the body and the fins, too.
Volcano killifish look really nice, and they got their name because they come from volcanic areas. This fish should live somewhere between three and five years in a fish tank setting with proper care.
Banded Panchax
The banded panchax is another fish that grows to be two inches long. They’re not that big, so keeping them in 10-gallon fish tanks will work out fine.
Expect a banded panchax to live for up to five years in a fish tank. This is a very peaceful fish that can easily have a place in a community fish tank.
They’re good choices for community tanks since they look nice. These fish are white and have black vertical stripes that go across their bodies.
You’ll see that they have some bright red at the end of their tails, too. This adds to the overall aesthetic appeal of the fish.
Can Killifish Live in Saltwater?
Most killifish live in freshwater, but there are some killifish that are different. There are a certain number of these fish that live in brackish water and saltwater.
Keep reading to learn about saltwater killifish. They may not be as common as freshwater killifish, but they’re still fish that you need to know about.
Saltwater Killifish
There aren’t that many saltwater killifish that people keep in aquariums. Even so, it’s still good to know about the options that you have.
Striped Killifish
The striped killifish is a fish that is found mostly in saltwater. You can find these fish living in the Chesapeake Bay.
They’re pretty big as far as killifish go. A striped killifish will grow to be up to eight inches long once it matures.
Since they’re fairly big, you’re supposed to keep them in 20-gallon fish tanks or something larger. Luckily, these are peaceful fish that can work out nicely in a community aquarium.
They’re also very easy to care for overall. They prefer waters with high salinity, and they can live between three and five years.
Mummichog
The mummichog is a killifish that can be found living in brackish water and saltwater. This fish is capable of adjusting to various salinity levels.
This fish isn’t specifically a saltwater fish, though. It can live in freshwater, but it’s also capable of tolerating saltwater.
So you have the option of keeping this fish in a saltwater tank. A mummichog will typically grow to be between three and three and a half inches long.
However, there are some cases where these fish will grow to be as long as 5.9 inches. They can be kept in 20-gallon fish tanks.
The normal lifespan of this fish is up to four years. This fish isn’t particularly aggressive.
Rare Killifish
Generally, killifish aren’t the most common types of fish. Some killifish might be seen in pet stores, but they aren’t as common as popular fish such as angelfish, guppies, and goldfish.
It’s not hard to find the most popular killifish being sold locally. You can easily buy golden wonder killifish, for example.
Many other types of killifish are a bit on the rare side. For example, pearl spotted killifish are a rare Middle Eastern breed that can be hard to find available for purchase.
Why are so many types of killifish rare? Simply put, some killifish don’t live long lives.
You see, many killifish live in bodies of water that go through dry periods. The water dries up, and the fish have to lay their eggs deep in the ground so they can survive until the water levels rise again.
These fish are known as annual killifish. Annual killifish have evolved to go through their life cycle rather fast.
They reach maturity fast because they need to be able to breed and lay eggs before the water recedes again. These fish might only live less than one year.
Semi-annual killifish live in bodies of water that occasionally go through dry periods. They’re similar to annual killifish, but they might live longer lives.
Non-annual killifish live in permanent bodies of water that don’t go through changes. These fish can live for many years, and many of them will live for up to four years.
This might help you to understand why some killifish are a bit rarer than others. The short lifespans of annual killifish make them harder to come by.
False Killifish
One thing that you should know is that there are fish out there that are referred to as killifish despite not actually being killifish. Killifish are egg-laying fish by definition, but some fish that are called killifish are live-bearers.
The two best examples of this are the least killifish and the diamond killifish. Below, you’ll learn a bit about them.
Least Killifish
The least killifish is a very colorful live-bearing fish. It’s known as the smallest live-bearer in the world.
It’s easy enough to take care of these fish at home. You can keep them in 5-gallon fish tanks easily.
Typically, the least killifish will live for up to three years in a fish tank. They’re omnivores that need to be fed a variety of foods.
People like buying these fish because they’re so easy to breed. Get the conditions right in the tank, and these fish will breed regularly.
Diamond Killifish
Diamond killifish are the other type of live-bearing fish that you should know about. In the wild, these fish are known to live in very shallow water.
They only grow to be around two inches long once they reach maturity. Most people who choose to keep them in home aquariums put them in 5-gallon tanks.
You can choose to keep a pair of these fish in a 5-gallon tank. However, they’re not easy to care for.
Many enthusiasts find these fish very challenging to keep alive in a fish tank setting. You should only buy these fish if you’re experienced and up for the challenge.
Final Thoughts
There are so many types of killifish to consider. You learned that most killifish are considered to be freshwater fish.
Some killifish can be found in brackish water and saltwater. There are even killifish that don’t technically qualify as killifish that fall into a “false killifish” category.
If you’re interested in buying killifish for your home, it’ll be wise to consider all of the options above. Those who are new to caring for these fish should stick to the beginner-friendly options.
Some of these fish are great for community fish tanks so long as you research compatibility. You should have a very good time keeping these fish in your aquarium.
Jeff has always enjoyed having pets, but as a child, he was drawn to his family’s fish tank. Being able to maintain a small ecosystem and observe the behaviors and interactions in the underwater world peaked his interest early on and has kept him hooked until this day. On Avid Aquarist, Jeff shares everything he’s learned about helping aquatic life survive and thrive in a home aquarium.