6 Best Saltwater Fish For Fluval Evo 13.5 (2023)

The Fluval Evo 13.5 is one of the best choices for nano tanks on the market. They are very popular for several reasons and can be a showpiece in your home or office.

If you are looking to set up a new or existing Fluval Evo 13.5, choosing suitable fish types can be a bit difficult as its small size will limit your options.

The dimensions of the Fluval Evo 13.5 are 22″ x 11.5″ x 15″ (L x W x H). The total water volume is 13.5 gallons.

These aquarium kits are fully upgradeable if you want to add other equipment to them and can handle certain corals with the included lighting.

A great tank choice for small fish and small corals.

Although your fish choices are somewhat limited, there are some great options for you to consider.

Also, this tank has a fully covered lid, so you won’t need to worry so much about fish that like to jump out of the tank, which is a big concern for open-top aquariums.

Here are 6 of the best saltwater fish for the Fluval Evo 13.5:

  1. Yellow Clown Goby
  2. Ocellaris Clownfish
  3. Neon Blue Goby
  4. Tanaka’s Pygmy Wrasse
  5. Yellowtail Damselfish
  6. Purple Firefish

#1. Yellow Clown Goby


Yellow clown coral goby isolated in aquarium

One of the best choices for smaller tanks is the Clown Goby. These small and peaceful fish are very colorful and will stand out in the Fluval Evo 13.5. The Yellow Clown Goby will grow to around 1.5″ and is entertaining to watch jumping around on the rocks. They will get along with most other tankmates and won’t bother any corals or invertebrates you may have.

The Clown Goby will appreciate having some branching coral in the tank which will replicate its natural environment. These fish are carnivores and will eat a variety of Brine shrimp and Mysis shrimp. They are affordable to purchase and will normally cost around $12 – $15.

#2. Ocellaris Clownfish

The Ocellaris clownfish is probably the most commonly kept clownfish in saltwater tanks. There are many different types of clownfish to choose from, including some rare designer clowns like the Snowflake Clownfish. But the Ocellaris Clownfish is affordable, easy to find, makes a great tankmate, and stays small, which is perfect for the Fluval Evo.

These fish will only grow to about 2″-3″ and you can keep a pair together in the Evo 13.5. Some people will argue that you can only keep one, but if you set up the tank properly with the right tankmates, you can keep a pair successfully. I normally recommend that a pair of clownfish only be in a 20-gallon tank, but if they are small, the 13.5 gallon Evo aquarium will work well.

They are also known to be active breeders, so if you have a pair it is possible for them to breed.

#3. Neon Blue Goby

Sharknose Goby (Neon Goby) on coral head
Sharknose Goby (Neon Goby) on coral head

The Neon Goby is a small fish that will only grow to around 2″ which makes it a great choice for the Fluval Evo 13.5. This Goby is dark blue with neon-colored strips running down the sides of their body. They are a peaceful fish and will get along with other peaceful fish and invertebrates. It’s important to only have one neon Goby per tank as they can be aggressive towards each other unless they are a mated pair.

They are also reef safe and will not bother your corals. The Neon Goby is a carnivore and should be fed a meaty diet including Brine and Mysis shrimp.

#4. Tanaka’s Pygmy Wrasse

If you are lucky enough to find one of these awesome fish, they are a great choice for the Fluval Evo 13.5. The Pygmy Wrasse is a stunning fish with tons of personality and color. They will grow to around 2.5″ and are a peaceful fish. They are easy to care for and require live rock formations and caves for them to hide in.

The Pygmy Wrasse is also a carnivore and should be fed a mix of frozen meaty foods. They will also accept pellet and flake food once they are comfortable and established in your tank.

#5. Yellowtail Damselfish

vibrant yellow tail damsel fish gets a closeup in a fish tank
vibrant yellow tail damsel fish gets a closeup in a fish tank

The Yellowtail Damsel is a very hardy and colorful fish that is easy to care for. Unlike other damselfish that are known for their aggressiveness, the Yellowtail Damsel is mostly peaceful, but it can be semi-aggressive towards certain fish.

This active fish has a blue body with a bright yellow tail and is reef safe. It will grow to around 2″ maximum and is an omnivore that requires a mixed diet of meaty foods. It will also eat algae and zooplankton present in your tank.

#6. Purple Firefish

Purple Firefish
Elegant Firefish (Nemateleotris decora), also known as the purple Firefish. Sea life.

As mentioned earlier, one of the great features of the Fluval Evo 13.5 tank is it includes a fitted lid that will prevent fish from jumping out of the tank. The Purple Firefish is one of those fish that can jump, so keeping them in this tank is a great choice.

The Purple Firefish is a unique fish that is peaceful with stunning markings. It is a somewhat slow-moving fish but can startle easily, causing it to dart quickly. They will grow to around 2.5″ and are a peaceful fish. They are reef safe and won’t bother corals or invertebrates. These fish are easy to care for and are affordable and readily available. They are commonly kept fish in a nano tank that is sure to be a source of conversation.

Read: 6 best saltwater fish for a 10-gallon tank

Tips for maintaining the Fluval Evo 13.5

Smaller nano tanks can be less forgiving with respect to maintaining water parameters versus larger tanks. There are a few extra maintenance tips to follow which will help keep your tank levels in check.

  • Maintain a consistent water change schedule
  • Don’t overstock or overfeed
  • Use plenty of water movement and filtration
  • Test water parameters frequently

These items are normal maintenance procedures for all tanks but are even more important for nano-sized tanks.

How many fish can I put in the Fluval Evo 13.5?

Due to the small tank size and dimensions, it’s important not to overstock the tank. I recommend only 3-4 small fish be added to this tank. Remember to keep a few members of a cleanup crew as well, which can add to your bioload.