Best saltwater fish tank

Fish & Reptile Supplies

Remember that every fish has its own needs. Do lots of research before purchasing fish for your saltwater tank in order to keep them healthy and happy.

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Which saltwater fish tanks are best? 

Saltwater tanks are the perfect way to add a little bit of marine magic to your space. The main draw of having a marine tank at home is all of the lovely options you’ll have when filling it with inhabitants. From colorful coral to vivid clown fish, saltwater tanks are often the first thing that comes to mind when someone thinks “fish tank.” 

Saltwater tanks are known for their beauty as well as their complexity. When dealing with marine fish and plant life, the water chemistry and temperature has to be just right in order to avoid fish casualties. Our top pick, the Fluval Sea Flex Aquarium Kit, is a solid 32.5-gallon tank from a very trusted brand in fish tanks that takes some of the complexity out of keeping a marine tank. 

What to know before you buy a saltwater aquarium 

Freshwater vs. saltwater tanks 

While most people envision a saltwater tank when asked to imagine a fish tank, the reality is that saltwater fish tanks are far less common in households compared to their freshwater counterparts. This is mainly due to the research and hard work that it takes to maintain a healthy marine tank. 

Marine tanks offer a lot more color variety than freshwater tanks. Seasoned aquarists love saltwater tanks for both the variety of options and the ability to grow their very own coral reef. 

If you are new to fishkeeping and aquariums in general, it could be a good idea to start with a freshwater tank and try your hand at a marine tank later on. This way, you’ll be well researched and will have learned a lot from your experiences. 

Tank size and inhabitants 

As with any fish tank, the size of the tank, normally measured in gallons, will dictate the amount of inhabitants that you can safely house. If you want to keep a larger community of fish, you should opt for a larger tank. 

The general rule of thumb when it comes to stocking your fish tank is that you should provide 1 gallon of water to every 1 inch of fish, but bear in mind that this is not a perfect rule. It is always best to understock your tank in the beginning and slowly introduce more fish with time. You will also need to take the individual needs of each species into consideration, and this includes your live plants or coral. 

Home decor and tank design 

A saltwater tank is going to become the centerpiece in any room, so make sure that you pick one that matches your personal decor and aesthetic. Pick a saltwater tank that comes with an aquarium stand or buy an aquarium stand that matches your space’s decor along with the tank. 

What to look for in a quality saltwater tank 

Saltwater tank starter kits 

A lot of popular fish tank brands sell their saltwater aquariums with everything you will need to get your tank started and cycled already packaged in with the tank. Most aquarium kits will not come with heaters, but they often come with the filtration system already installed. 

Good filtration system and space for a heater 

When choosing a tank to use as a saltwater fish tank, one of the most important things to look for is a quality filtration system. The filtration system of your aquarium can make or break your experience with the tank. 

Another important factor to consider is whether or not the tank has space to be modded or accommodate a heater. Most marine fish are tropical fish and will require warm water. If your tank doesn’t have a hidden compartment for a heater, you’re going to end up with a somewhat clunky and unfinished-looking aquascape. 

LED grow lights for coral 

If you plan on keeping a planted marine tank or trying your hand at growing coral, you will definitely need a good set of LED grow lights built into your tank. Most tanks come with great built-in LED lights. If your tank does not include LED lighting that is sufficient for marine life, make sure that there is space in the hood or above the aquarium to add more lights. 

How much you can expect to spend on a saltwater tank 

Saltwater tanks can range from $150-$600. 

Saltwater tank FAQ

Where should I keep my saltwater fish tank? 

A. The tank should be kept in a low-traffic area on a flat surface that is away from windows, doors, vents and air conditioning units. 

What is the cheapest way to measure the salinity of my saltwater fish tank? 

A. The least expensive method of measuring water salinity is by using a hydrometer. 

What’s the best saltwater fish tank to buy?

Top saltwater fish tank 

Fluval Sea Flex Aquarium Kit

Fluval Sea Flex Aquarium Kit

What you need to know: This kit from Fluval has everything you need to get started and is perfect for experienced aquarists. 

What you’ll love: This tank takes some of the headache out of keeping a marine tank thanks to its full-spectrum Marine 3.0 LED lights that can be controlled from an app. This tank is sure to make any fishkeeper happy with its extra space for mods and add-ons. Comes with filter media to help get the tank started.

What you should consider: This tank is on the more expensive side, so be sure to do your research before purchasing. 

Where to buy: Sold by Amazon 

Top saltwater fish tank for the money

Fluval Sea Evo V Saltwater Fish Tank Aquarium Kit

Fluval Sea Evo V Saltwater Fish Tank Aquarium Kit 

What you need to know: This smaller sized tank from Fluval is bargain priced and perfect for novice aquarists. 

What you’ll love: This tank makes for a great first foray into saltwater tank keeping. It comes fitted with Fluval’s powerful 3 stage filtration system. 

What you should consider: The tank doesn’t come with a heater, but it has space for one in the back compartment. 

Where to buy: Sold by Amazon 

Worth checking out

GankPike 12-Gallon Saltwater Aquarium

GankPike 12-Gallon Saltwater Aquarium 

What you need to know: This stylish, bullet shaped aquarium is the perfect tank for aquarists that are new to marine tanks. 

What you’ll love: The tank comes with a heater as well as a great LED lighting system. 

What you should consider: Some users have stated that they needed to upgrade the heater. 

Where to buy: Sold by Amazon


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Addison Hoggard writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.


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