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Do you ever look at a fish tank and think, “Wow, I’d love to have something like that at home”? Well, you’re not alone. Many people love the idea of having their own aquarium. But when it comes to choosing fish, things can get a bit tricky. There are so many different types to pick from!

We’ve got everything from tiny, colorful guppies to big, bright goldfish. Not to mention the super cool neon tetras, the tough little Betta fish, and the unusual but fantastic angelfish. Each of these fish has its own needs and personality, so it’s important to choose the right ones for your tank.

Read on and we’ll talk about what you need to think about when picking your fish, like how big they’ll get, how well they’ll get along with each other, and how much care they need. Plus, we’ll look at some common mistakes people make so you can avoid them.

Introduction to Popular Aquarium Fish Species

Are you clueless about the right freshwater fish to put in an aquarium? Below, let’s talk about five of the most popular species worth considering. 


Often referred to as the “rainbow fish” due to their myriad colors, guppies are small, active, and relatively low-maintenance freshwater aquarium fish. They typically grow to about 1-2.5 inches in length. One key aspect of guppies is their sociability. 


They’re schooling fish, which means they prefer to live in groups. Single guppies can become stressed, which might affect their health. In terms of diet, they’re omnivores, happily munching on both plant matter and proteins. They will readily eat flake food but also appreciate the occasional treat of brine shrimp or bloodworms.

Neon Tetras

Neon Tetras are renowned for their vivid, iridescent stripes that shimmer under aquarium lights. Their small size (typically 1-2 inches) and peaceful nature make them a popular choice for community tanks. Neon Tetras are schooling fish and prefer to be in groups of at least 5 or 6. 

They thrive in slightly acidic water with low light conditions and enjoy plenty of hiding spots provided by plants or aquarium decorations. Neon Tetras are omnivores and eat a diet of small pellets or flakes, as well as freeze-dried or live foods. 

The average lifespan of Neon Tetras is about 5-10 years with proper care. Consistent water quality, a balanced diet, and a stress-free environment are crucial factors in achieving this lifespan.


The humble goldfish is a classic and popular choice for many aquarium enthusiasts. Goldfish are larger, typically ranging from 1 to 14 inches in captivity depending on the variety, and are known for their hardiness and vibrant colors. 

Despite their reputation as simple pets, goldfish actually require a fair amount of care. They’re messy eaters and produce a lot of waste, necessitating a robust filtration system. Goldfish are omnivores and thrive on a diet of specially formulated goldfish pellets or flakes, along with regular servings of fresh, leafy greens and veggies.


They typically grow to around 3-5 inches and coexist well with soft corals, adding diversity and visual appeal to your setup. While they are relatively easy to care for, they do not require a sea anemone to survive in captivity.


They thrive on a variety of foods, including flakes, pellets, and frozen foods. Despite their adaptability, remember that saltwater aquariums require specific water parameters and thorough maintenance. Always consider each species’ specific needs for a successful aquarium setup.

Betta Fish

With their spectacular fin displays and range of colors, betta fish is a unique addition to an aquarium. They typically grow to about 2.5 to 3 inches. Male bettas are solitary fish and, due to their aggressive nature, should be kept alone. 

However, female bettas can live together in a “sorority” with careful monitoring. Betta fish are carnivores and require a high-protein diet. They’ll enjoy betta-specific pellets and the occasional treat of live or frozen daphnia, brine shrimp, or bloodworms.

Factors to Consider When Choosing Fish

After learning about different fish species, it’s time to think about which ones will make the best fit for your aquarium. But how do you decide? Here are some key factors to consider:


Not all fish get along. Some are peaceful and love company, while others prefer solitude or can become aggressive with certain tank mates. It’s crucial to choose fish that can coexist peacefully. For example, guppies and neon tetras are both peaceful and could potentially share a tank, while a betta fish might need a space of its own.

Neon tetras


Bigger fish need more room to swim and grow. They also produce more waste, which means you might need a more robust filter. When thinking about size, remember to consider the adult size of the fish, not just their size when you buy them.

Care Level

Some fish are hardier and easier to care for, making them perfect for beginners. Others need specific conditions or diets and are better suited for experienced fish keepers. Make sure to choose fish that match your level of experience and the amount of time you can devote to caring for them.


Different species of fish have different lifespans. Some fish may only live for a few years, while others can live for a decade or more. Consider how long you’re planning to keep your aquarium and choose your fish accordingly.

blue fishes and corals


Lastly, consider the aesthetic appeal of your chosen fish. The color, shape, and movement of your fish can have a big impact on the overall look of your aquarium. Balance is key here. Try combining different types of fish to create a visually interesting and harmonious environment.


Picking the right fish for your aquarium can feel overwhelming, but with a solid understanding of different species’ needs and compatibility, the task becomes much simpler and enjoyable. Whether you’re captivated by guppies, goldfish, neon tetras, betta fish, or angelfish, remember to consider their unique requirements and your ability to meet them.

Fishkeeping isn’t just about owning pets; it’s about creating a thriving underwater world that reflects your dedication and care. By understanding and embracing this, you’re already on your way to becoming a successful aquarist.