Nano tanks are rapidly growing in popularity due to their size and perceived low maintenance level, although they often require more cleaning and maintenance than larger tanks. However, not every fish is cut out to live in a 3-gallon tank. Some fish grow too large for a tank this small, and other fish become extremely stressed in an environment that does not allow for lots of space for swimming or hiding. Some fish need to be kept in groups that are too large for a 3-gallon tank.
Picking the perfect fish for your 3-gallon tank isn’t impossible, though. There are some great options for fish that can happily live in a tank that size if you are up for the challenge of keeping the tank clean and well maintained. The frequent cleaning and maintenance of a 3-gallon tank aren’t for the faint of heart, though, so carefully consider your nano pets before you bring them home.
Table of contents
10 Best Fish for a 3-Gallon Tank
Guppies are brightly colored, playful fish that are always active, making for a lively tank. They are small fish that are easy to care for, making them good for beginners and small tanks. They enjoy living in groups but are not true shoaling fish, so you don’t have to fill your 3-gallon tank with a full shoal of Guppies. Be aware that they reproduce quickly and in large numbers, so for a tank this small, it’s best to keep a female-only or male-only tank.
2. Endler’s Livebearers
These small Guppy cousins also come in many bright colors and can be extremely eye catching. Endler’s Livebearers reproduce at the same rate as Guppies, so plan to keep a male-only or female-only tank if all you have is a 3-gallon tank. They don’t need large groups to be happy, so plan on 4 – 6 fish in a 3-gallon tank. An added benefit of Endler’s is that they typically prefer smaller environments to larger ones.
3. Cherry Shrimp
The name gives away that this isn’t a fish, but Cherry shrimp are exceptionally fun and come in a whole host of colors, not just red. You can keep a few dozen Cherry shrimp per gallon of tank space, so a 3-gallon tank can safely hold quite a few. These shrimps are active and when their environment is well-maintained, they begin reproducing, but they are unlikely to overpopulate the tank. They do have a relatively short lifespan, which can help keep their population under control.
4. Ember Tetras
Ember Tetras are a tiny Tetra variety that love to school. Their bright orange coloration is flashy and will definitely be noticeable in a tank of any size. In the wild, these fish live around the roots of trees in blackwater environments, so giving them swimming space in a well-planted tank with driftwood is a great way to ensure their health and happiness. They are a little more sensitive than some of the hardier fish on this list, though, and are more of a moderate care level in a 3-gallon tank.
5. Chili Rasboras
Slowly increasing in popularity, the Chili Rasbora is one of the smallest fish available in the aquatics trade, making them perfect for nano tanks. They are shoaling fish, so plan to keep a group of at least six fish. They are cute because of their size, but they pack a punch with color and can bring a lot of activity to your tank. Provide them with plants and swimming space to help them feel safe and comfortable.
6. Zebra Danios
This beginner friendly fish can be perfect for a nano tank with the proper care. Zebra Danios are hardy fish that should be kept in shoals of at least six fish. They can be kept in smaller groups, but this often leads to stress for the fish. For a 3-gallon tank, stick to Zebra Danios instead of one of the other varieties of Danios, though. Zebra Danios are one of the smallest and easiest varieties to care for.
7. White Cloud Mountain Minnows
White Cloud Mountain Minnows are shoaling fish that prefer cool water, so you can get away with no heater in your tank for these fish. They are beginner friendly fish that breed readily, so you may need a backup plan for the fry if they begin reproducing in your 3-gallon tank. These fish do like to have some open swimming space, so they aren’t the best pick for a nano tank, but with the right setup, their colorful bodies can really enhance your tank.
These tiny catfish are great for controlling algae! Be prepared to get a group of them, though, since this helps them feel safe. They are social fish that don’t like to be alone. Since you’ll need a group of Otocinclus in your 3-gallon tank, they will likely be the only fish you have space for. However, they’ll happily snack on the algae in the tank all day and the more you keep, the more social and interesting they will be.
9. Neon Tetras
One of the most popular freshwater fish, Neon Tetras are brightly colored and easy to care for. They are shoaling fish and are quite social and interesting to watch in a group. They aren’t the best choice for a 3-gallon tank, but if you provide a setup similar to what the Ember Tetra prefers, then you’ll have happy fish. Make sure you are maintaining high water quality to ensure the health and longevity of these fish.
10. Betta Fish
Bettas are one of the most beautiful fish you can get, and they come in tons of color morphs and tail shapes. Typically, it’s recommended to keep Bettas in tanks that are at least 5 gallons, but some Bettas are perfectly happy in well-maintained 3-gallon tanks. Make sure you provide lots of plants, hides, and enrichment in the tank to keep your Betta feeling secure but not crowded.
A 3-gallon tank isn’t a whole lot of space, so choose your tank pets with care. If you overstock a tank of this size, you’ll not only be doing water changes multiple times per week, but you’ll also be risking the health and happiness of your fish. A nano tank is a commitment of time to ensure it stays in excellent shape and the water quality stays high. However, if you’re willing to make the commitment to the care required by a nano tank, you’ll be rewarded with a beautiful tank of happy fish.
Featured Image Credit: Yan Cabrera, Pixabay