Best Fish for Beginners to Keep in A Small Tank

By Eddie Waithaka @aquariawise

Best Fish for Beginners to Keep in A Small Tank

Fish tanks are rewarding but come with a steep learning curve.

So if you are a newbie, you’ll want to start with easy fish in a small tank. Guppies, tetras, rasboras, minnows, betta, danios, otocinclus catfish, mollies, platies, and danios are all ideal options for small tanks and are easy for beginners.

Goldfish grow too big and produce excess waste, needing a big filter pump and consistent water change. As such, they are not ideal for newbies, regardless of their popularity.

You ideally want a large tank (30 gallons) and fish with a small bioload that will remain stable and big enough for easy water changes. You can also use the same tank for advanced fish in the future.

What are The Easiest Fish to Care for in A Small Tank

If you are new to the hobby and wondering what fish is right for you, granted most newbies start off with a small starter tank, consider any of the fish below:

1.Guppies are hard to kill and breed pretty fast.

2.Betta are colorful and will live in a 2.5 to 5 gallon.

3.Neon and cardinal tetras are peaceful, small, and easy to maintain but are sensitive and require a fully matured tank.

4.Mollies require a 20-gallon and can be challenging to breed.

5.Platies colorful and different strains can mix but can be challenging to breed.

6.Otocinclus are tiny algae-eating fish and a favorite bottom-dweller for small tank

7.Cories are peaceful and easy to care for.

8.Bristlenose plecos are unique add-ons to a small to medium-sized fish tank.

9.Shrimp and snails

15 Fish Best for Beginners in A Small Fish Tank

Here are all the fish I recommend beginners to start with in a small starter tank. Most do not grow too big and are easy to care for. Many are hardy and will survive newbie, rookie mistakes.

Betta Fish (Siamese Fighting Fish)

Betta fish is a good choice for a beginner looking to venture into the aquarium lifestyle. The fish are colorful, some with short fins and others long. The color range is also expansive, with white, blue, red, orange, and more.

You will need a 5 to 10-gallon tank, a heater, and a filtration system for your fish. You can include plants, shrimp, and snails with a betta, but males should not be paired with other fish.

An aggressive betta will attack and kill tankmates, and keeping it alone is always the best choice.

Add lots of plants that will cover the surface of your fish tank and create a canopy similar to the marshes your bettas live in the wild.

Your betta might kill shrimp in the tank depending on individual aggressions, but many will just let the shrimp be unless you starve them.

Snails are mostly ok, especially betta-proof types, such as sun, thorn, nerite, and horned nerite snails.


Guppies have long been good beginners’ fish. Colorful, easy to care for and breed, and only requires a small tank for a decent school to thrive.

However, guppies have recently been populated with weak, in-break fish, so if you decide to try them as your first fish, purchase them from a reputable breeder with a good history of his fish.

If you manage to get a good deal, guppies are fun and hardy fish to start in a 5 to 10-gallon if you have never kept fish in an aquarium before.

You can fit up to 10 guppies in a 10-gallon fish tank as long as you have a reliable filter and do regular water changes. Replace 10 percent of your tank capacity two or three times a week.

Notably, better water quality gives your guppies better vivid colors and nicer genetics.

Bare in mind that when you mix male and female guppies, they will breed and increase your numbers rapidly, which may be overwhelming if you are keeping fish for the first time.

To manage breeding guppy numbers, you would require a bigger tank (more than 10 gallons) and better filtration. Get more male guppies if you do not want your school to breed.

Guppies are peaceful reserves to a few nipping. They will live with many tropical freshwater fish and critters, such as shrimp and snails. However, adding fish and shrimp with your guppies will increase the bioload, so you might need to reduce your numbers or get a larger tank.

Add plants in your guppy tank to provide coverage and lower the fish stress levels. Aquarium-safe rock, slates, and driftwood are also ideal.

Do not overfeed your guppies since they have tiny bellies, and you might kill them, and watch the water parameters to keep your fish happier.

Neon Tetras

Neon tetras are tiny, peaceful, colorful, and readily available fish. They are gorgeous, and you will love watching their schooling behavior. Neons are not hardy and are sensitive to water quality (require a fully matured tank), but that does not mean, as a beginner, you can not consider them.

Neons are schooling fish that need to be kept in a group of 6 fish in a 10 to 15-gallon tank. The fish requires a warm tank, so you will require a heater and a reliable filter to clean the tank.

A rectangular or square aquarium works better because your tetras will have more water area to swim in schools and allow oxygen to get into the tank better than a circular or hexagonal tank.

If you’ve got a larger tank and decent-filtration, you can put as many neon tetras as your heart desires (within reason), even as a beginner. The fish can also accommodate many tropical tankmates, including shrimp and snails.

Neon tetras do better in planted tanks with decorations and driftwood. They are also one of the few tropical fish that like water darkened by tanning, similar to the waterways they occupy in the wild.

Otocinclus Catfish

Otos are good bottom-dwelling fish for tiny tanks. They are valued algae eaters and perfect for beginners because of their relative ace of maintenance.

These little catfish are often in demand and sell out pretty fast in pet stores, so they are not as abundant as other species in this list.

As mentioned, otocinclus are perfect algae cleaners suitable for small tanks that other algae eaters will outgrow.

However, remember to supplement your otocinclus diet with wafers to keep them nourished regardless of how much algae is in your aquarium. If you need to remove more algae from the tank, stock more of these catfishes.

Fortunately, Otos do not overfeed, so they are safe even when there is excess food and algae in the fish tank, but remember leaving wafers and veggies in the tank too long will pollute your water and kill your fish.

Otos are also sensitive to water and dietary changes of often die when moved from the pet store to a home tank if not acclimated properly.

Ember Tetras

Embers tetras are another nano fish that make a perfect beginner’s choice. These little finnies look amazing, contrasting against green plants in groups, and you can have up to 8 embers in a 10-gallon starter tank and up to 50 in a large tank paired with other colorful tropical fish.

Large numbers of embers naturally look like jewels inside your tank if you feed them, but ensure you offer them the right food to bring out their colors.


Note that embers tend to school less in smaller tanks taking away their aesthetics, so try to get a larger tank (20 gallon+) if you are yet to purchase one to get the best from your finnies.

And if you like your tetras to swim in unison, as they do in the wild, an even bigger tank is required (50 gallons+) with plenty of open water.

Remember that all tetras, including embers, are capable fin nippers, though smaller species are less likely to cause damage. So, to help your tetras feel secure and keep them from becoming aggressive, add several tetras to your fish tank.

Chilli Rasboras

Chilli rasboras are hardy fish that make perfect beginner fish in small tanks and are easy to care for, though not often recommended by fish store owners.

Their maintenance is straightforward, with a slight learning curve and room for rookie mistakes.

You only need to know about the nitrogen cycle and keep up with water changes to successfully own chili rasboras.

They find safety in numbers, so keep them in groups of at least 6 individuals, though larger groups of 20+ are best when you have enough space.

Your chili rasboras should take about a month after shipping to color up if well cared for. Feed them the right food and raise them in soft, acidic, tannin-stained water to represent their natural habitat.

Chili rasboras are hardy and not prone to diseases but can be impacted by inappropriate water conditions in a fish tank, so ensure the quality of your water remains pristine.

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