Good Fish for Starting a Tropical Fish Aquarium

An illustration of good starter fish for an aquarium

Illustration: © The Spruce, 2018

Nothing is more exciting than adding fish to a newly set up aquarium. However, the choices you make now will have a big impact on your success or failure. Unfortunately, many new fish owners make the wrong choices, lose some or all of their fish right off the bat, and give up on fish keeping.

That doesn't have to happen to you. The two biggest errors made when stocking a new aquarium are adding too many fish at a time and choosing the wrong fish. Tip the scales in your favor by following these basic, but important, steps.

How Many Fish?

When you are standing there drooling over all the beautiful fish at the pet shop, remember one word—moderation. In most cases, only two or three fish should be introduced to a tank initially. Once the nitrogen cycle is established and the tank is stable, additional fish can be added.

However, the same rules apply when adding the next round of fish. Moderation, moderation, moderation: you must add only a few at a time. If there is nothing else you remember when adding new fish, it’s moderation.

Factors in Choosing Fish

Fish owners tend to go for fish with the most physical appeal. Not that pretty fish are always poor beginner choices, but there are other important factors to consider. A good beginner fish should have these qualities:

  • Tolerate a variety of water conditions, particularly the conditions during startup
  • Accept a variety of foods, and are easy to feed
  • Will not reach grow to be overly large
  • Are not aggressive
  • Are compatible with a variety of other fish (unless you want a single species tank)

Small schooling fish are generally good first fish, but take care to not add an entire school at once if the tank is brand new. If you want more than one species, don't start them all at the same time. Instead, build one school up before starting the next.

Tetras are one schooling fish to avoid in a new tank. Most are more sensitive to water conditions than other fish, and often will not survive the initial start-up cycle. It’s generally best to wait until the tank is a bit more mature before adding Tetras.

Good First Fish List

Although the list seems small, there is quite a variety to choose from. Once your tank matures, you can branch out into other species of fish. Wondering why your favorite fish isn't on the good first fish list? Here’s why some popular fish are absent from the list.

  • Catfish (some varieties): Many catfish are sensitive to the start-up cycle, or grow too large to be good first fish. For example, the common Pleco is a hardy fish, but it gets very large. The Otocinlus is small but very sensitive to toxins that are present in a newly started tank.
  • Goldfish: Goldfish are cold water fish that produce a lot of waste, which means they require a larger tank all to themselves. The proverbial goldfish bowl isn't an ideal home for the goldfish. If you want a goldfish, give it a nice roomy tank with just goldfish in it.
  • Live bearing fish: If you have children, you may be tempted to get live bearing fish. Because they require special conditions (most notably salt in the water) and are more susceptible to disease, they are not ideal first fish. If you do opt for live bearing fish, choose one species only. Select your fish very carefully at the pet store and provide them with the appropriate care and habitat for that species.

At the Fish Shop

Now that you've decided on the species of fish, there is one more important step–choosing healthy fish. When you go to the shop, don't take just any old fish. Look them over carefully.

Avoid fish with wounds or nipped fins as they are more susceptible to disease. Check the eyes. Cloudy eyes are a sign of poor water conditions and or disease. Don't get fish with sunken bellies, as they have been underfed or may be suffering from a disease.

Making good first fish choices can make all the difference in your new tank