Sometimes the sheer volume of the genus, species, and varieties of aquarium fish can be mind-boggling- If not overwhelming, especially for novice aquarists. We’ve created a super simple, birdseye view of popular aquarium fish, grouped by category and family, to make it easy to get an overview of this huge subject.
The outline below provides beginning aquarists with a map and reference point, and experienced aquarists with a visual for considering their next species.
I’ll be slowly filling in more fish, and linking to our profiles on each. The main groups are freshwater and saltwater fish, both broken down into families (such as cichlids or labroids) and their individual fish; Then we move on to other aquarium groups, like invertebrates, plants, and corals. Check it out!
Table Of Contents
1 Freshwater Fish
This group encompasses a wide variety of fish and temperaments with the most famous being the goldfish of the cyprinid family: A laid-back fish in multiple varieties, each with a voracious appetite and the ability to quickly dirty a tank as a result!
Among aquarists, cichlids are highly popular despite their aggressive tendencies, since their bright colors are a creative addition to a tank. These fish originate primarily in Africa and South America, with a small handful of exceptions.
Characins are another family popular in aquariums, the rummy-nose tetra and neon tetra being probably the best known of this group.
Beginners will want to check out the livebearers section for the much-beloved guppy, a beautiful, friendly, hardy fish that’s the perfect beginner aquarium addition. And with some thoughtful planning, a loach can be an excellent bottom dwelling aquarium tank mate!
Horse head/face loach
Pangio Kuhli loach
Rummy nose tetra
Metriaclima (Pseudotropheus) Lombardoi
Blood Parrot cichlid
Lake Malawi cichlids
Cynotilapia pulpican- Kingsizei
Metriaclima (Pseudotropheus) Lombardoi
Lake Tanganyika cichlids
Cyprichromis leptosoma Mpulungu
Tanganyikan Goby Cichlid
Tropheus brichardi kipili
Tropheus bulu point
Black Moor Goldfish
Black Oranda Goldfish
Calico Ryukin Goldfish
Red oranda Goldfish
Redcap Oranda Goldfish
Microrasbora sp. “Galaxy”
Rasbora heteromorpha- Harlequin
Poecilia sphenops (Molly)
- Guppies are studied by scientists for their model evolutionary biology.
2 Saltwater Fish
Saltwater aquariums and reef tanks are often regarded as too difficult for beginners to start with, and in some ways that’s fair- But a small, well-planned tank with enough time spent researching and learning, and a saltwater tank is definitely within reach for most people.
When it comes to color in your tank, saltwater fish really bring it. The elegant firefish (also called a purple firefish, or purple goby) has a color combination unlike any other, and yellow tang provide an incredible neon yellow flash in any aquarium.
The added element here in terms of parameters and maintenance is salinity. Just like freshwater fish, saltwater fish need their aquarium to replicate their natural environment as closely as possible. And, like any other fish, the parameters of saltwater fish vary, so don’t plan to put a bunch in the tank without making sure they’re a good match!
3 Brackish Fish
A little bit of saltwater, a little bit of freshwater.. This is how brackish fish roll. In the wild, their natural environments are places where freshwater meets saltwater (like where the river meets the sea). Estuaries, floodplains, even rivermouths are the spots these creatures call home.
Brackish fish can tolerate some fluctuation in salinity, but it’s best to keep them in the salinity that’s closest to that of their natural environment.
Worth noting that this isn’t the best place for beginning aquarists to start: Cut your teeth on a small freshwater tank, and then slowly work your way up to more complex tanks. Intermediate and advanced aquarists will enjoy the depth of a new brackish tank project.
Green Spotted Puffer
Green Spotted Scat
Red Spotted Scat
4 Freshwater Invertebrates
These spineless wonders are often overlooked by aquarium hobbyists, but they have their own contribution to make! For example, cardinal shrimp and Sulawesi shrimp in general have just as much eye-popping color as any tropical fish.
Cherry shrimp are the best to learn with as they’re inexpensive, hardy, and breed easily. A word of advice when getting started with shrimp is – like fish – to start with inexpensive ones first, so if you make a mistake you’re not out all that money for that fancy ornamental shrimp!
Snails in general get a bad rap, because they can reproduce easily and take over a tank before you know it. But if you keep them in check, don’t overfeed, and monitor them, they can be a highly useful addition since they’re detrivitores – They eat decaying and dead matter floating around the tank. Which sounds gross, but in the animal world, they’re the clean up crew you want on your team!
African Filter Shrimp
Blue Pearl Shrimp
Caridina sp. “Crystal Red”
Caridina sp. Cardinal
Green Lace Shrimp
Red Nose Shrimp
Golden Apple Snail
Zebra nerite snail
5 Saltwater Invertebrates
No aquarium project is complete without plants! (I guess that’s not entirely true- There are some pretty cool rocks out there!) But really: Plants bring a pop of vibrant green dimension and can contribute to a healthy ecosystem, adding oxygen to the water and helping to mimic the fishes’ natural habitat.
One thing to note: Just like matching fish that are appropriate to live together, you have to match plants and fish! Some fish will eat or otherwise disrupt your plants. Similarly, aquatic plants have their own water parameters necessary for them to thrive.
Some are great for starter aquariums, like the easy-to-keep Java moss: It grows fast and quickly spreads, and it’s easy to take care of. Others are best for experienced aquarists, like utricularia graminifolia, a very picky carpet plant that feeds on plankton as prey.
Anacharis elodea (Waterweed)
Hornwort (Ceratophyllum Demersum)
Nymphaea ‘Tiger Lotus’
Ohhh… ahhh.. CORALS! These saltwater creatures never fail to enchant. And yes, they’re a creature: It might look like a fancy rock, but corals are very much alive!
Corals are comprised of a bunch of individual animals called polyps– That big round thing you see on corals is actually the polyp’s mouth, and coral polyps eat everything from tiny organisms to small fish.
Some fish aren’t coral safe or “reef safe,” such as wrasse, gobies, and angelfish. Gobies, for example, can dig and damage coral. Others may actually try to eat the coral.
One thing that I tend to view as a fundamental principle of fish keeping is that no matter how hard we try to replicate a creature’s natural environment, we can’t do it exactly. Most fish and corals would not have otherwise been placed in such a small space in the wild. As a result, anything could happen, and you really have to keep an eye on how fishes respond. The best short write-up on this IMO is from the Saltwater Aquarist Blog, and you can read it here.
Acanthastrea Coral- moon coral
Euphyllia divisia- Frogspawn
Pavona (Cactus Coral)
Pipe Organ Coral
The sheer volume of aquatic species makes this post an impossible task, but I hope to continue to build it out in the spirit of the original site as much as possible. Adding saltwater invertebrates and plants sections, adding more species, and creating more profiles are all on the giant to-do list that just seems to get bigger! But hopefully this will give beginners a solid overview to get the lay of the land, and provide advanced aquarists with ideas for their next tank.