Best* Saltwater Aquariums

Small saltwater aquariums—often referred to as “nano” tanks—can be a fun type of habitat to keep for those experienced in the hobby. The smaller size means maintaining proper water parameters can be significantly more challenging—but the breathtaking species that thrive in a smaller aquarium can be well worth the hard work.


Pet Parent Faves

Petco sells a wide variety of some of the best all-in-one saltwater aquariums, along with food, accessories and the saltwater pets themselves. Here are the best-selling kits.

Fluval 5-Gallon EVO V Marine Aquarium Kit


5-Gallon EVO V Marine Aquarium Kit

This small saltwater aquarium has impressive performance in a nano package. The 11,000K LED lighting is suitable for keeping many types of coral. It also includes a 3-stage filtration system with oversized media to help keep the water crystal clear.

This is one of the best reef-ready aquariums and is great for coral that only needs a small amount of room. The filtration is concealed neatly to provide an ultra-sleek look, and lighting can be adjusted with a convenient touch start. This aquarium is a great choice for fitting into a small space such as a desk or table.

  • 21.3” L X 8.3” W X 12.5” H
  • Mechanical, chemical and biological filtration
  • Displays coral reefs beautifully
  • Makes a tranquil eye-catcher for your office
  • 2-year limited warranty

Fluval 13.5-Gallon Evo XII Marine Aquarium Kit


13.5-Gallon Evo XII Marine Aquarium Kit

This kit is ideal for the pet parent wanting something slightly larger than a desktop aquarium but who still doesn’t have much space to devote to a tank. The Fluval 13.5-Gallon Evo XII Marine Aquarium Kit may be the answer.

Powerful 14,000K reef-capable LED lighting and the 3-stage filtration system included in this kit have the same performance features as aquariums significantly larger. This is one of the best all-in-one saltwater aquariums and can allow you to set up an impressive underwater oasis sure to be the envy of your aquatic-loving friends.

  • 23.4” L X 13.5” W X 15.6” H
  • Silent 3-stage filtration
  • 2-year limited warranty
  • Ideal for coral or small saltwater fish
  • High LED output

Coralife 32-Gallon LED Biocube Aquarium


32-Gallon LED Biocube Aquarium

The Coralife 32-Gallon LED Biocube is an excellent choice for someone looking for one of the best large saltwater aquariums. This setup is sleek and innovative, with an inclusive design. It includes LED lighting that displays multiple settings controlled by a timer to simulate sunrise/sunset and moonrise/moonset and full daylight with color enhancing LEDs.

Accessing your aquatic life is easy with a hinge-top canopy that folds back as needed. Filtration is customizable with a quiet submersible pump, easy refugium setup and dual intakes with an adjustable return nozzle

  • Available in 32-gallons or 16-gallon tanks. The 32-gallon tank is 22” L X 23.88” H X 24” W. The 16-gallon tank is16.75” L X 20.13” H X 18.13” W.
  • Compatible with all existing Biocube accessories
  • Integrated 24-hour timer with three independent channels
  • Ideal for saltwater or freshwater setups
  • Bright white for daytime, and sparkling blue moon glows for nighttime

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Learn More About Saltwater Aquariums

It’s good to know exactly what type of fish you want to keep to determine the best size for your saltwater aquarium. For instance, if you’ve decided to keep clownfish—the clownfish tend to be hearty compared to other delicate saltwater creatures, so this would be a great option for beginners—you would want at least a 20-gallon habitat, and you want to add 10 more gallons for every fish you add.

If you’re planning on keeping more than one fish or a reef tank with fish in it, make sure it accommodates everything comfortably and they’re compatible. If you plan to get a more aggressive species of fish and have more than one in the habitat, the more room you can give them the better. A too-small aquarium can upset even the most peaceful species, and their quality of life may suffer. You may also want to pick a tank that can accommodate fun aquarium décor.

Aquarium kits like the ones listed above are excellent options for beginners. They usually have everything needed to get started and are great tools to learn from. It’s also important to have the proper tools on hand for aquarium maintenance.

Keep in mind that the smaller the aquarium is, the harder they are to maintain, so if you’re unsure how much time you will have to devote to your new pets, the larger-gallon aquarium kit will be a better choice. You also have to make sure your tank size is suitable for the pet you’re keeping—for example, the 5-gallon kit is suitable for reefs, but most saltwater fish wouldn’t thrive in such a small tank.

When choosing your pet, you may want to adopt a low-maintenance fish to start out. Damselfish are considered to be very hearty, and they come in beautiful colors. Goby fish are a species that is considered to be very peaceful, so they may also be good to start out on. Petco has a variety of live saltwater fish in a rainbow of colors.

Petco sells an array of excellent aquariums, and they all can be great choices, depending on their usage. The absolute best way to give your pet the best home is to educate yourself on their needs, and Petco can be a great resource.

Our animal care sheets are designed to help you find out exactly what you need to do to ensure your new scaly friends are living their best lives. We also have a large selection of saltwater fish food and top deals on some fishy accessories.

*Based on sales data.