Skip to main content
Saltwater Fish

Best Fish For 30 Gallon Saltwater Tank

By December 17, 2020June 5th, 2021No Comments
best fish for 30 gallon saltwater tank

One of the most popular sizes of saltwater tanks is 30 gallons. This is on the larger end for smaller aquariums, and most hobbyist would not consider it to be a nano tank. This makes it a suitable size for beginners, and it is not something you have to invest a lot of money in. You are able to get a nice assortment of marine fish, and of course, you can even put some corals in it to make it a reef tank.

A common size for a 30 gallon breeder tank is 36 X 18 X 12. This size and volume of water that go in your tank will determine which types of fish and how many you can add. As with any size tank, there are certain fish that can and cannot inhabit it. Some fish will grow too big, and they will need to be moved to a larger aquarium. Understanding which marine fish can inhabit your tank is important to understand so that your aquarium can thrive and be successful.

Below, we will review some of the best fish for a 30 gallon saltwater aquarium.

How Many Fish Can I Put In A 30 Gallon Tank

You can put about 30 inches of fish in a 30 gallon tank. The amount you can add depends on the size of each fish, and it is a good idea to go under 30 inches especially if you don’t have great filtration. An example would be 8 3-inch fish as this puts you right under the 30 inch limit. Another factor to consider is that you may have fish that grow.

If you have 3 small chromis at 2 inches each, their mature size with equal 12 inches which would be almost half the total for a 30 gallon saltwater tank.

6 Best Fish For 30 Gallon Saltwater Aquarium

1. Clownfish

clown fish in 30 gallon tank

The clownfish is a staple for almost any saltwater tank, and it is a perfect choice for a 30 gallon saltwater tank. When you are dealing with this size tank, you have limited space. You are not going to be able to add dozens of different species of marine fish. Knowing this, you want to make sure you get the best options.

Clownfish are popular, and it is one of the most recognized marine fish thanks to the movie Finding Nemo. These fish are hardy and easy to care for which makes them perfect.

One of the best reasons to get clownfish is due to their behavior in your aquarium. Some marine fish just mindlessly swim back and forth. A pair of clownfish will interact with each other, and they will almost “dance” together sometimes underwater. When they see you near the tank, they will swim to the front in anticipation of food.

The standard one that everyone recognizes is the Ocellaris Clownfish (Amphiprion ocellaris ). This is the orange, black, and white version, and you can get a captive-bred one. This means that it is more hardy, and you are not taking one from its natural habitat of the reef.

These fish are reef safe, so if you plan to put corals in your tank, these fish will do great. There are many different specimens and colors available inluding Fancies, Flurries, and Black Storms.

Reasons To Get A Clown Fish:

  • Popular
  • Low Cost
  • Hardy
  • Interactive
  • Reef Safe

2. Yellow Watchman Goby

yellow watchman goby fish
Sitron, CC BY-SA 3.0, via Wikimedia Commons

The Yellow Watchman Goby is one of the most interesting marine fish, and because of this, it makes a great choice for a smaller tank. When space is limited, you want to get the best fish that you can. If you are not familiar with the goby, it will build a burrow as a home in your sand bed. You can watch it move in and out of its hole, and it does this interesting thing by sifting sand.

The Goby will sift sand through its mouth and pass them out of its gills. He will leave little piles of sand all around his burrow. This helps to aerate your sand, and it also provides nutrients.

The Watchman Goby is a unique fish that does not simply swim back and forth in your tank. It is unique, and it gives you a diffferent type of fish to watch in your tank.

You can also get a pistol shrimp to pair with your goby. These two will form a symbiotic relationship, and they are fun to watch together. The shrimp will keep the burrow in order, and it will dig it out for the two of them. The yellow goby will stand watch over the shrimp and their home to warm the shrimp of predators and danger.

This pair will keep your aquarium interesting for you and your guests, and they are suitable for a 30 gallon tank.

Reasons To Get A Watchman Goby:

  • Unique
  • Peaceful
  • Low-Moderate Cost
  • Reef Safe

3. Blue Green Chromis

chromis saltwater fish

Chromis are a great choice for 30 gallon aquariums because you can have something that groups together. While these are not technically schooling fish in a home environment, they will definitely shoal together which is close to having a school of fish. You can get 3 of these chromis and they will stay together which will add some spectactular color to your tank.

These marine fish will group together, and when they swim, it makes for a colorful splash of blue-green. Chromis are beginner friendly, and they are easy to obtain. Almost every local fish store carries them, and you can get them online as well. They are one of the least expensive marine fish to put in aquariums.

Another great aspect of these fish is their voracioius appetite. Once the fish food hits the water, these guys will be first in line for dinner. They are very active and a thrill to watch during feeding time.

Often, budget is one of many reasons to have a 30 gallon saltwater tank, and if costs is a big factor, then these are the right fish for you. You can often get 3 of these for $30-$45 which is a low price for marine fish.

Reasons To Get A Blue-Green Chromis:

  • Low Cost
  • School/Shoal Together
  • Great Feeders
  • Reef Safe

4. Firefish

Rickard Zerpe, CC BY 2.0, via Wikimedia Commons

The firefish (Nemateleotris magnifica) is a popular marine fish for aquariums due to its coloration and long fin. This peaceful fish is a great tank mate for smaller aquariums because it is peaceful and easy to care for. You will need a lot of live rocks in your aquarium because when it is frightened, it likes to hide there. This also goes by Fire Goby, Fire Dartfish, and red fire goby.

An adult firefish will get up to 3 inches, so that is something to consider, although that is not much bigger than the average purchase size of 1 to 2 inches. This is a perfect size for 30 gallon aquariums. These fish will sometimes try to swim at the surface and jump when they are stressed. A good cover on your tank will help with that.

You should only keep one of these in your tank unless you have a mated pair because they can be aggressive toward its kind.

Reasons To Get A Firefish:

  • Great Personality
  • Low Cost
  • Peaceful
  • Reef Safe

5. Royal Gramma Basslet

royal gramma basslet
Georges Jansoone (JoJan), CC BY 3.0, via Wikimedia Commons

The royal gamma is a great marine fish, and it is beginner friendly as well. It has a beautiful purple and yellow color pattern, and it will only get a few inches long. This makes it perfect for 30 gallon saltwater tanks.

This is also a peaceful fish which is important when you are limited on space, and other fish can feel threatened when others get close to them. They do like to hide out in your rocks sometimes, but they do come out especially during feeding time.

It is best to keep one due to it being territorial.

Reasons To Get A Firefish:

  • Reef Compatible
  • Colorful
  • Peaceful

6. Six Line Wrasse

Six Line Wrasse Marine tank fish
Georgina Jones, CC BY-SA 4.0, via Wikimedia Commons

The Six Line Wrasse (Pseudocheilinus hexataenia) is a very active fish that will do great in a 30 gallon saltwater tank. It weaves in and out of your live rock, and it can even be seen taking a nap in one of your rock holes if you have one big enough. They are graceful swimmers as they weave in and out of cracks and crevices. It is certainly colorful and fun to watch.

This wrasse will generally stick to itself as it is a loner, but it more than makes up for it by its ability to swim in and out of your live rocks.

A lot of wrasse are not reef safe, but the Six Line will do great in a reef tank. It is generally considered a peaceful fish, but it may be a little aggressive toward other wrasse if it is not fed well, and it will need plenty of places in the rocks to hide when stressed.


My name is James, and I am the founder of Saltwatercoraltank. I love everything about the ocean, and my main hobby is saltwater aquariums. Currently, I have 3 tanks that I maintain. I have a 130 gallon mixed as my main, and I prefer softies.

Leave a Reply