Bettas and goldfish are two species of popular fish that many home fish keepers would love to see living together in the same tank.
When initially considering a tank setup, it’s important to remember that just because two fish species look beautiful together, this doesn’t mean that they’ll necessarily get along!
Our goal today is to take a look at some of the similarities and differences between betta fish and goldfish, along with a few different fish species you may want to consider.
Follow along and we’ll share how to keep our pet goldfish and betta fish happy and content when they neighbor in the same aquarium.
Can Goldfish and Betta Live Together?
The short answer to this question is yes, but with some major caveats. While betta fish and goldfish can strictly speaking live together in the same tank, the more aggressive behavior of bettas coupled with the larger spatial needs of goldfish mean that this may not be the best arrangement.
Just because both fish interact well with humans, this doesn’t mean that they’ll get along with each other!
From a biological standpoint, betta fish are a true tropical fish and therefore prefer warmer temperatures, while goldfish are largely considered a cold water fish. This difference in needs can be difficult to manage in one tank, and the danger of causing a dangerous temperature shock is real.
Would A Betta Fish Kill A Goldfish?
While a betta fish wouldn’t normally kill a goldfish, there are many other things to keep in mind when looking at their compatibility in general.
Do They Get Along?
Regardless of fish personality, bettas and goldfish do not get along due to their different habitat and dietary requirements. When keeping goldfish living with betta fish, a bigger tank can be a good first step towards fostering good tank mates.
In order to have betta fish live with goldfish, compromises may need to be made which can affect the health of both for the worse.
The warmer temperatures required for betta fish can lead to goldfish becoming more easily sick or infected with parasites, and colder temperatures can do the same to your healthy betta.
Betta Fish Basics
Also known as Siamese Fighting Fish, the Betta splendens that many know and love has an undue reputation as an aggressive tropical fish. Wild bettas were first found in the warm water of Thailand and eventually made their way to the domestic market in the mid-1920s with the explosive growth of hobby aquariums.
In reality, it is the male betta fish alone that earns this reputation as a fighting fish, defending its territory with vigor and battling other fish during breeding seasons. Male bettas are quite the fin nippers, and will use both a display of fin and gill expansions and actual combat to get their way.
Captive bettas bear little resemblance to their wild counterparts, having been changed through captive breeding over many generations into the beautiful creatures we see today.
A fish with its fins nipped may have trouble swimming, and more dangerously may appear to be injured when actually sick with a disease such as fin rot.
As a general rule, any pet fish suspected of disease such as fin rot or swim bladder disease should be immediately placed in a quarantine tank for observation.
Betta fish are an adaptive, hardy fish when it comes to tank size and can tolerate conditions from a tiny bowl up to a larger tank system.
Bettas live up to 3 years.
Betta fish grow between 1 and 2.5 inches in length, depending on the size of the tail. If you need more info about betta size, here’s my article about how big can a betta fish get.
Betta fish are carnivorous in nature, living solely off protein such as fly larvae, brine shrimp, and scraps of small fish. Unlike goldfish, a betta fish can never have too much meat!
When considering attitude, it’s important to note that bettas tend to be more solitary in nature. These tropical fishes will attempt to face off against others which they perceive as threats to their territory or mates.
Warm fresh water with varietal substrate, much like their native waters of Thailand and Cambodia in Southeast Asia.
If you’re interested in keeping bettas, here’s my article on what type of water do betta fish need. Despite being one of the hardiest freshwater species, they need the right type of water to thrive.
Today’s common goldfish, or Carrasius auratus, is a small fish compared to its ancestor, the wild Prussian Carp of central Asia.
The wild carp was originally domesticated and bred for their meat, but breeders eventually found that by selecting for looks they could find success in selling to private collectors.
These new fancy goldfish greatly outshone their progenitors, and paved the way for the aquariums of today.
Goldfish lifespan dramatically differs from that of betta fish. When properly cared for, a goldfish will live around 10-15 years but can live for up to 25! Learn more about the factors that affect their lifespan and how to improve it with this “How Long Do Goldfish Live?” article
Typically between 1.5 and 2 inches, but can reach up to 14 in a large enough tank!
For more information, our article on how big do goldfish get offers more details on goldfish size.
Unlike bettas, goldfish prefer an omnivorous diet, meaning that they can eat a variety of both plants and proteins.
Goldfish are considered a very friendly fish, and can easily get along with most other fish.
Cooler water temperature with rocky or varied substrate.
When considering tank setup bettas and goldfish generally require different conditions in order to thrive, but there is some overlap in the things that make them most comfortable.
Goldfish prefer a more open space in which to swim, while bettas like to hide themselves away in nooks and crannies between rocks and plants.
A tank that makes one fish happy may lead to the other being less comfortable, and as such it may be best to create a separate tank environment altogether for each.
For betta fish, a 2-gallon tank is the recommended minimum betta fish tank size to give an adequate amount of space, with 5-10 gallons being highly recommended. Remember, just because a betta can survive in a tiny space doesn’t mean that it will enjoy it!
Goldfish prefer more room, and a 20-gallon tank is the recommendation. Considering that a goldfish can reach upwards of 20” in length if given space, it is also important to remember that spatial needs may change as the fish grows over the course of its life.
As previously mentioned, betta fish and goldfish ideally prefer different water temperatures, making keeping both in the same tank a challenge.
Being cold water fish, goldfish generally enjoy water temperatures ranging between 60 and 75 degrees.
However, they are adaptable and can tolerate warm water up to 80 degrees. Betta fish, on the other hand, do not typically do well in temperatures outside of their comfort range of 75-85 degrees and may suffer as a result of wide fluctuations.
Goldfish have a reputation as an extremely dirty fish, producing large amounts of waste that can lead to ammonia spikes in tank water and even cause ammonia poisoning in other fish. As such, extreme attention must be paid to conditions and frequent water changes should be considered.
When monitoring the tank, look at the water surface for excess growth (ie scum). Frequent partial water changes are key to avoiding ammonia poisoning in the tank and keeping the fish tank clean is a top priority.
Considering the large amount of waste that goldfish can produce, having a filter with a strong flow is important to consider.
Unfortunately bettas are not the strongest of swimmers, and may have difficulty moving around in a tank with a high amount of water movement.
A compromise when trying to keep both goldfish and betta fish in the same tank can be a small, low-powered bubbler to filter the betta tank while allowing them to move easily through the water. Read this Do betta fish need a bubbler article if you want to learn more about bubblers.
Betta Tank Mates
Given their reputation, it may come as little surprise that betta fish can be a challenge to pair with proper tank companions when shopping around pet stores
“Can you put two betta fish together?” has been a question for many fish keepers. Well, Betta fish prefer relative solitude, and as such extra space can be helpful in keeping other inhabitants safe from their territorial aggression.
Female bettas are generally much calmer than males, who will begin fighting as soon as they see one another.
As such, we recommend finding a female when choosing to have betta fish live with goldfish.
Goldfish Tank Mates
A highly social creature, the goldfish can get along with many different species of fish. As a community animal, these fish can actually suffer when living alone. We suggest having at least one other fish to keep the goldfish properly stimulated and healthy in the long term.
An important (albeit grisly) factor to keep in mind is the goldfish are omnivores and will attempt to eat any fish that can fit in their mouths including your beautiful bettas!
Is it worth keeping a Betta and Goldfish together?
While betta fish and goldfish can technically live together in the same tank, it must be noted that this can come with great difficulty and health risks to both fish. As such, we recommend that betta fish live with goldfish as a last resort if an emergency arises in one of their separate tanks.
Here’s a video of betta fish and goldfish together in a tank
The fact that bettas require a temperature that is on the high end of the range at which goldfish can live, along with the increased threat of diseases caused by waste makes it hard to recommend keeping the two together.
Throughout today’s article we have seen that the key components deciding the happiness of our fish (temperature, attitude, environmental needs,) differ greatly between goldfish and betta fish.
Trying to manage all of these factors can be incredibly difficult, even for the professional and we would not suggest it to the casual aquarium owner.
As always thank you for taking the time to read this piece, I wish you the best of luck on your aquarium adventure and remember to share with any other fish fanatics you may know! If you’re looking for accessories for a 20-gallon tank, we also have helpful reviews about filters, heaters, and hoods.
- “10 Best Tank Mates for Your Goldfish in a Freshwater Aquarium.” Aquarium Coop, https://www.aquariumcoop.com/blogs/aquarium/goldfish-tank-mates.
- Brough. Animal-world. Animal World. Retrieved Nov 16, 2021, from https://animal-world.com/.
- FishBase. Retrieved Nov 16, 2021, from www.fishbase.se.
- Innes, Williams. Innes’s Exotic Aquarium Fishes. TFH Publications, Inc. 1994.
- Masloski, Arthur. “Goldfish: Myths Debunked.” Tropical Fish Magazine, Jan. 2009.
- Skomal, Gregory. Saltwater Aquariums for Dummies. New York City, Hungry Minds, Inc. 2002.
- Ward, Brian. The Aquarium Fish Survival Manual. Hauppage, Barron’s Educational Series, Inc. 1985.