Everything You Need to Build a Kick-Ass Fish Tank, According to an Aquarium Expert

The facts, filters, and fish you need to know when putting together a tank.

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Dogs and cats are great. But don’t count out fish. Sure they’re not as interactive as Fido or Max, but they’re a pet that provide a lot of good for kids.

For instance, fish tanks are a great introduction to STEM subjects. The connection to biology and ecology is obvious, sure, but there’s also a good deal of engineering fundamental to the pipes, pumps and filters aquaria require. And in terms of care, fish need regular feedings, tank cleanings, and water changes to survive. Having a fish tank is also a great way to introduce urban and suburban kids to nature and open up conversations about such topics as death. While some species can live for years, others naturally have short lifespans even when perfectly cared for.

As the world of aquaria can be a bit intimidating for beginners, we sought fish tank advice from Matt Pedersen. A senior editor and associate publisher for two aquarium magazines, AMAZONAS and CORAL, he’s been a fish owner since age five, and has introduced both of his kids to the world of aquaria. He is a true believer in the advantages of keeping fish as pets and provided us with not only advice for keeping a proper fish tank but also recommended the right gear for the job.

Start with freshwater

Freshwater fish tend to be less delicate than their saltwater counterparts. Oceans are relatively stable environments, so saltwater fish don’t adapt well to change.

As Pedersen points out, “If you’re living in a river, it rains, there’s a huge flush of cold water and the water chemistry changes within minutes.” Freshwater fish are therefore more resilient because they’re used to such sudden changes. They’ll also be more forgiving of any amateur mistakes you make.

Take maintenance seriously

Being a good fish owner means maintaining a healthy environment in the tank. The most important part of that process is managing the water quality. Filtration breaks down fish waste into non-toxic elements, but even those can dangerously alter the water quality in large quantities.

“Routinely diluting the aquarium water with freshwater is the number one essential husbandry task you have to do as an aquarist,” Pedersen says. He recommends performing 25 percent water changes on a weekly basis. Never change all the water, as you’ll be removing all of the good bacteria that naturally keep it clean.

Another important task: scraping algae off of the sides of the tank, a hands-on chore that kids are more than capable of.

Find an independent retailer you like and stick with it

Pedersen advises picking “a local fish shop (LFS) the same way you’d pick a doctor or dentist; ask a friend, read reviews, do your research. Go in and talk to them; look at their tanks and see which ones emulate what you’re dreaming of.” Chain stores might be more convenient for some, but the quality of the advice you’ll get will probably be lacking. “You’re not going to get the same knowledge and understanding and support time,” Pedersen says.

A common mistake beginners make is going to different stores, where they might receive incompatible fish, products, and advice. Pedersen says that finding one shop with salespeople you trust and reviewing independent publications (like the ones he edits) is the best way to build up basic aquarist knowledge and skills.

Think long-term

According to Pedersen, the average lifespan of a person in the aquarium hobby is 18 months. The biggest reason? People don’t know what they’re getting themselves into. Do your research, and don’t make any impulse purchases. Like with any pet, you shouldn’t get a fish if you aren’t able to invest the time and energy needed to care for it.

The Best Fish Tank Gear to Buy

A Starter Tank…

Pedersen calls 10-gallon tanks “the de facto starter size.” Why? They’re small enough to fit on a countertop and weigh about 100 pounds when full. This model from Aqueon is made of glass, a less expensive and harder to scratch material than acrylic, and has a simple black frame around the top and bottom

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…Or An All in One Tank Option

All-in-one kits have become increasingly popular, according to Pedersen. They include the tank along with lighting and filtration systems, though the plug-and-play way of doing things may ultimately be not as edifying as building a system yourself.

For a freshwater all-in-one kit, Pedersen recommends kits like this one by JBJ. Their 10-gallon kit comes with a tank, heater, gravel, thermometer, plants and other products that will help you start and maintain a healthy environment for freshwater fish.

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If you’re set on a saltwater tank, Biota makes an all-in-one kit that goes even further: it comes with everything you need to get a 13.5-gallon tank going including two compatible clownfish shipped right to your door.

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The Filter to Buy

There are two styles of filter to consider for your first tank. Hang-on-back models cling to the outside of the tank. Internal filters sit directly in the water. “They all get the job done,” Pedersen says, “and they all largely consist of the same elements.” Absent a strong brand recommendation, he did mention Fluval, Marineland, and Hagen as names to consider in addition to this hang-on-back Whisper IQ Power Filter from Tetra.

Buy Now $15

Natural Gravel

Pedersen is similarly agnostic about gravel brands, as there are only a few suppliers and they all get the very basic job done. The main thing gravel does for a tank is contribute to its aesthetic, which is more important than it might seem.

“A natural aesthetic, particularly one that is reminiscent of the natural environment where the fish you’re keeping are normally found, will help the fish display the best colors and behaviors,” says Pedersen. Kids may be drawn to gaudy, neon tank elements but they aren’t good for the fish and don’t fit with most people’s decor so they don’t tend to last as long as aquascapes that showcase the natural beauty of the fish. This 20-pound bag of CaribSea black gravel fits the bill and is the top seller in the category on Amazon.

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Get Yourself Some Glofish

Glofish are fish that have been genetically modified with a fluorescent protein chain isolated from a jellyfish. They glow in a completely unnatural way, but Pedersen says that kids love them. You can buy them in groups or as individual fish, like this pink tetra.

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Or Stick to Some of These Other Finned Options

Pedersen polled his staff and got a bunch of different recommendations for beginner fish. The commonalities were mostly things to avoid: fish that grow too large, fish that are susceptible to disease, predatory fish, and fish with personalities that are nippy, territorial, and/or aggressive.

A big factor in the success or failure of a tank is the water. Since changing water frequently is so important, it’s much easier to maintain a tank if you can add tap water to your tank, so you want fish that will do fine given the particular makeup of your local tap water, particularly its hardness and chemicals added by your water utility. But no matter the composition of the water, you’ll almost always need to pre-treat it with some sort of dechlorinator or water conditioner. Your local fish shop can recommend the correct products for your water.

More generally, Pedersen recommends community fish like swordtails, tetras, danios, and gouramis. Community fish are fish that are less particular about their environment either because they’re naturally indifferent to the kind of water they live in or they’ve become so domesticated that they don’t need what they needed in the wild anymore. You can also typically have more than one kind of community fish coexisting peacefully in the same tank.

One species to consider: White Cloud Mountain Minnows. They can do well in a wide variety of water conditions and temperatures.

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