Can You Keep Koi Fish in an Aquarium?

While some koi fish hobbyists would argue that the best environment for keeping koi fish is an outdoor pond, this isn't a possibility for all koi fish owners. Unfortunately, not everyone has the space required to dig an outdoor koi fish pond in their backyard. Sure, we'd all love to be able to build a koi fish pond in our backyards, creating the perfect space to observe these beautiful fish, but this isn't an option in all cases.

If you've dreamed of owning a collection of koi fish but have thought that this was impossible due to not having enough space, keeping your fish in an aquarium is a viable option. Today, Koi Fish USA will be sharing some helpful tips that you should consider if you'll be keeping your koi fish in an aquarium. With this information, you can set forth with confidence! Let's get started.

Finding the Appropriate Koi Aquarium Size

One of the first questions koi fish enthusiasts must ask themselves is what size their koi fish aquarium should be. This is an essential consideration because koi fish require a large enough space to grow properly and swim freely. Even if you only support one koi fish in your aquarium, you'll want to be sure that you have a large enough aquarium to host your fish. As a general rule of thumb, bigger is often better when it comes to koi fish aquariums.

Put simply, koi fish are relatively large fish. While your koi fish may not be massive when you first purchase them, they have the potential to grow up to 36" in length. While the exact size of your koi fish will vary based on the environment, you can count on them growing to at least 2 feet when supported in a healthy environment. For this reason, it's best to choose sizing for your koi fish aquarium based on the size that your koi fish will be in a year, not necessarily the size that they are now.

There are a few different calculations that you can use to estimate the most appropriate koi fish aquarium size. The generally accepted rule of thumb is that you'll need approximately 10 gallons of water for every inch of fish. Another calculation that you can use is providing one cubic foot for each inch of fish. Here's a basic guideline you can follow when estimating the best size for your koi fish aquarium:

  • Small Koi (2" to 8"): 100 to 150 gallons
  • Medium Koi (8" to 14" ): 250 to 300 gallons
  • Large Koi (14" to 24" ): 400 to 500 gallons
  • Jumbo Koi (24" to 36" ): 750 to 900 gallons

 Regarding the guidelines above, you'll also want to consider a few other factors when determining the best size for your koi fish aquarium. By asking yourself the following questions, you can make the best choice in terms of koi fish aquarium size.

  • How many koi fish do you plan on hosting in your aquarium? The more koi fish you'll have in your tank, the larger it will have to be to support them.
  • Are you going to add plants? You'll want to have a large enough aquarium to provide enough space for the plants while also allowing your koi fish room to swim freely.
  • Will you be adding features to your aquarium? The more features you plan to add, the more space you'll need.

What's the Best Temperature For Your Koi Fish Aquarium?

After you've determined the right size for your koi fish aquarium, you'll want to find the optimal water temperature to support your koi fish. Koi fish are sturdy fish that are capable of surviving in pretty extreme temperatures. Still, the optimal temperature for koi fish is anywhere from the mid-60s to mid-70s in Fahrenheit. But why is it so important to find the right temperature for your koi fish aquarium?

There are many benefits to finding the optimal temperature for your koi fish aquarium. For one, it's suitable for supporting the healthy growth of your fish. Secondly, however, it also limits the number of harmful bacteria in the water, which can cause health issues. Finally, water between the mid-60s and mid-70s holds dissolved oxygen better, ensuring that your fish will have enough oxygen to be healthy.

So how can you ensure that your koi fish aquarium is always at the optimal temperature to experience these benefits? For one, you'll want to make sure that your aquarium is kept out of direct sunlight. Much like a backyard pond, too much direct sunlight can substantially warm the aquarium's temperature over time, which isn't suitable for your koi fish. If your koi fish aquarium will be placed near a window, it's a good idea to provide plenty of shade from the sunlight.

Put simply, you'll want to do your best to ensure that there is minimal chance for rapid changes in water temperature because, although koi fish can handle slight variations in water temperature, drastic changes that occur rapidly will only stress them out. Stress is very unhealthy for koi fish.

What Type of Filtration Will You Need For Your Koi Fish Aquarium?

Another prime consideration to make when setting up your koi fish aquarium is filtration. Koi fish can be very messy fish, and they can produce a significant amount of waste. For this reason, the importance of proper filtration cannot be understated if you want your koi fish to be happy and healthy in the aquarium. To best support your koi fish in their new home, you'll need to use both biological filtration and mechanical filtration. Additionally, some aquarium filtration systems will also use chemical components to assist with waste management.

No matter what, the filtration system you choose for your koi fish aquarium should be equipped to keep up with waste production. Your chosen filtration system should be able to cycle the entire volume of the koi fish aquarium 3 to 4 times within an hour. Filtration is a vital part of keeping your koi fish healthy, so it's highly recommended that you look into the best koi fish aquarium filtration systems when setting up your aquarium.

More Koi Fish Aquarium Tips to Consider

Finally, we thought we'd close this article by offering a few additional koi fish aquarium tips that you should consider. If you take these tips into account, you'll have much more success setting up your aquarium to best support your prized koi fish. When you take the time to make sure your aquarium is suitable for your koi fish, you can be confident that you'll be able to enjoy your fish for many years to come. Here are a few more important things that you need to know.

  • Consider the size of your aquarium stand: If your aquarium will be sitting on a base, be sure that it is sturdy enough to support not only the aquarium itself but all of the aquarium's contents. An aquarium gets much heavier once you add water, aquarium features, plants, and of course, your koi fish. The last thing you want is the whole aquarium toppling over due to having a too flimsy stand to support its weight.
  • Keep your aquarium covered at all times: Koi fish are notorious for jumping, especially when stressed. Be sure that your koi fish aquarium is covered at all times to prevent a serious accident.
  • Add substrate: As many koi fish enthusiasts will tell you, using gravel in your aquarium that is too rough and jagged can actually injure your koi fish. Koi fish are well-known for their foraging habits, so make sure to add substrate so that there is a smooth surface in your aquarium suitable for their curiosity.
  • Watch over your cats and dogs carefully: Believe it or not, your curious pets may prove dangerous to your koi fish. While your cats and dogs may only want to get near your koi fish aquarium out of curiosity, this can quickly turn into a tragic accident. Watch over your pets closely to be sure that your koi fish are protected.

Fill Your Koi Fish Aquarium With the Best Fish From Koi Fish USA

Now that you know some of the key considerations to make when setting up a koi fish aquarium, you may be wondering where the best place to buy koi fish for sale online is. Luckily, you've found us here at Koi Fish USA!

At Koi Fish USA, we have over 25 years of experience in the online koi fish industry. We've used our knowledge and expertise to offer the healthiest, safest, and most beautiful koi fish on the market. Check out our selection today and choose the best koi fish to fill up your new aquarium! By selecting one (or several) of our prized koi fish, you'll be setting your aquarium up for success.

Whether you're a seasoned koi fish owner or are starting your collection for the first time, we provide the best standard koi, butterfly koi, and goldfish for any aquarium or backyard pond. Browse our selection today, and feel free to contact us with any questions! We'll be more than happy to assist you.