Can you meet the needs of goldfish and tropical fish in the same aquarium? Or is this just a recipe for disaster?
Your betta is lonely, so you add two goldfish to keep him company. Or maybe you already have a goldfish tank set up, and you’re planning to buy neon tetras for a little more variety.
But can goldfish and tropical fish really thrive together in one tank?
After all, you don’t want to subject your goldfish to more stress than they can handle. Or worse, come home to find satisfied and bulging bellies but no goldfish to be seen!
For some pet owners, goldfish get along fine with tropical fish. Others have tried relentlessly to keep their goldfish in a tropical environment, only to discover fish go missing, torn fins, disease outbreaks, and a number of other problems – all problems that could have been prevented if their goldfish had their own separate tank.
So what’s going on?
Are Goldfish and Tropical Fish Compatible?
In short, no.
I definitely wouldn’t recommend keeping goldfish with tropical fish, and I know several fish hobbyists who wouldn’t either. Goldfish aren’t tropical.
It isn’t just a matter of how goldfish get along with other tropical fish. Goldfish and tropical fish have different requirements and to meet both requirements in one tank is just impossible. You can’t do it. You might come close, but you can’t give your fish all of the recommended goldfish care they need in a tropical aquarium.
You’ll have to make compromises to keep both your goldfish and tropical fish happy.
- Maybe you can’t give your goldfish a complete nutritional diet because you also have to meet the needs of your tropical fish.
- Maybe you can’t provide your goldfish with a powerful enough filter to reduce waste and maintain high oxygen levels because the water flow would irritate sensitive tank mates.
- Or maybe you can’t maintain the comfortable temperature conditions your goldfish prefer because your tropical fish are too sensitive to cooler temperatures.
If you’ve been keeping goldfish and tropical fish together for years, you might think this article doesn’t apply to you.
Think again. Your fish appear to be getting along fine, but what’s really happening in the aquarium that you don’t know about?
8 Reasons Why You Shouldn’t Mix Goldfish and Tropical Fish
- Goldfish and tropical fish have different temperature requirements. Goldfish – coldwater fish – prefer cooler temperatures around 65°F (18°C), while tropical species like their water toasty warm (72 to 85°F or 22 to 29°C). Yes, a goldfish can stand warmer temperatures temporarily (when they’re kept in a pond during summer months). But they won’t feel comfortable kept in warm water all the time. And if you try keeping tropical fish in cold water, they’ll just become lethargic and refuse to eat. One of the many benefits of keeping goldfish is that they don’t need a heater; most tropical tanks do.
- Goldfish and tropical fish have different temperaments. Goldfish are peaceful, while many tropical fish can get very aggressive. Some fancy goldfish varieties also have long, flowing fins that other tropical species love nipping on. Since goldfish are rarely ever aggressive, it’s not uncommon for several smaller fish to bully larger goldfish. And if you have territorial fish in the aquarium (angelfish, for example), it’ll be a living nightmare for your goldfish. Your goldfish could become seriously hurt or even killed.
- Goldfish and tropical fish have different disease tolerances. Some diseases affect fish differently. Since tropical fish are a completely different species, there’s a good possibility that your goldfish will get sick from a disease that won’t necessarily impact your tropical fish. Goldfish also get diseases more readily under warmer temperatures than they would under cooler, more comfortable temperatures.
- Goldfish and tropical fish have different diets. Without the right nutrients, your goldfish may not thrive. Many may even become malnourished, which can lead to all sorts of goldfish diseases. Goldfish require more fiber-rich foods in their diet to prevent constipation (very common in fancy varieties). Young and fancy goldfish also require protein-rich foods to develop and grow. To top that off, goldfish are primarily plant-based and so need plenty of veggies. Since goldfish don’t have “true” stomachs, they often run into digestion problems. Tropical food is harder for goldfish to digest than food specially formulated for goldfish.
- Goldfish are ravenous eaters. Goldfish won’t think twice before gobbling up every morsel of food you drop into the tank – and greedily pushing aside slower fish that stand in their way. Unlike bettas, goldfish aren’t picky at all. And because they feed so quickly and thoroughly, some tropical fish (especially the smaller ones) won’t stand a chance during feeding time.
- Goldfish are messy. Goldfish excrete lots of waste that can quickly pollute a smaller aquarium (which is why they’re kept in large tanks). Most tropical fish don’t need the extra space goldfish do and so are usually content in smaller aquariums. And because many tropical tanks have filtration systems that can’t keep up with the high levels of waste your goldfish excrete, you’ll soon find yourself with devastating and dangerous ammonia spikes that can cause serious problems – even killing your fish.
- Goldfish are very large compared to many tropical fish species. Most fancy goldfish varieties grow up to 6 or 7 inches long (15 or 18 centimeters), while common and comet goldfish can grow to a foot long (30 centimeters) and even more. Though there are exceptions, tropical fish tend to stay small. By the time your goldfish reach adulthood, your tropical fish may turn into tasty snacks.
- Goldfish love the company of other goldfish. While goldfish don’t form very tight schools like neon tetras, they are still quite social and like to be around other goldfish. In fact, you may notice that your goldfish stick together and will often follow one another around the aquarium. Even so, certain goldfish varieties still shouldn’t be mixed; goldfish do best when they’re with other goldfish similar in size and shape.
Still in Doubt?
Think about this: You wouldn’t go to the beach on a hot summer’s day in a winter coat. And why would you? You’d be much too warm, sweaty, and very stressed out.
Putting your goldfish in a tropical aquarium is going against their nature.
Just like you wouldn’t feel comfortable wearing a coat in 80-degree weather, your goldfish could go through all kinds of stress in a tropical aquarium. And shouldn’t you provide goldfish with an aquarium habitat as close to their natural environment as possible? After all, you don’t want the hassles of sick or lethargic fish.
It’s ultimately up to you whether to mix goldfish with tropical fish, but remember: Your goldfish depend on you for their care. If you want happy, healthy fish with vibrant colors and long-lasting lives, you’ll think twice before throwing goldfish into a tropical tank.
So What Do You Think?
Should you mix goldfish and tropical fish together? Should goldfish care be compromised to satisfy tropical fish needs? Or should goldfish be kept in separate tanks with other coldwater fish?
Join the debate! Add your thoughts, feedback, and goldfish care tips to the comments below.