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What Fish Can I Keep? Aquarium Quiz

Take our interactive quiz to find out exactly what fish you can keep based on your tank size, experience level, and goals.

Quick Answer

The biggest mistake beginners make is buying fish based purely on how they look in the store. Many beautiful fish (like Oscars or Plecos) grow to be massive and require huge tanks. Others (like Discus) are extremely fragile and require expert-level water parameters. By answering a few simple questions about your setup, we can recommend hardy, appropriate fish that will thrive in your specific tank.

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Question

Walking into a fish store can be overwhelming. There are hundreds of species, and unfortunately, many pet store employees will sell you fish that are completely incompatible with your tank.

Why Tank Size Matters

A 5-gallon tank is completely different from a 50-gallon tank. A 5-gallon tank is only suitable for a single Betta fish or some shrimp. It cannot hold Tetras, because Tetras need horizontal swimming space to school. If you put active swimming fish in a tiny tank, they will become stressed, aggressive, and susceptible to disease.

Experience Levels

Some fish are 'bulletproof' and can survive the common mistakes beginners make (like forgetting a water change or slightly overfeeding). Zebra Danios and Guppies fall into this category. Other fish, like German Blue Rams, will die if the water temperature drops by 2 degrees or if nitrates rise above 10ppm. We strongly recommend sticking to 'Beginner' fish for your first year in the hobby.

Frequently Asked Questions

Can I keep a Betta fish with other fish?
Yes, but it depends on the tank size and the Betta's personality. In a 5-gallon tank, a Betta must be alone. In a 20-gallon tank, you can often keep a Betta with peaceful, fast-moving, dull-colored fish like Corydoras or Harlequin Rasboras. Never put a Betta with fin-nippers like Tiger Barbs.
What is the easiest fish to keep alive?
The Zebra Danio is widely considered the hardiest freshwater aquarium fish. They can survive a wide range of temperatures, pH levels, and beginner mistakes. White Cloud Mountain Minnows are a close second.