What Can Live in a Desktop Reef Tank?

Selecting animals for a small reef tank under 5 gallons is all about intentional choices, balance, and long-term success. Stocking a desktop aquarium requires careful planning and research. This blog will dive into some important factors to keep in mind, and break down some stocking ideas for our most popular tanks.

Our 5 Gallon Small-In-One XL is the smallest size that supports clownfish, and even then, we recommend a very small pair and moving them if they outgrow the tank.

First, Let’s Set Expectations

A small reef tank works best as a coral-first system. While yes, it is possible to keep both invertebrates and fish in a small aquarium, it's incredibly important to keep livestock numbers low in order to not overwhelm the system. Fewer animals result in more stable water parameters, less stress on the tank, and a better experience for both the aquarist and the livestock.

Corals That Thrive in Desktop Reef Tanks

Soft corals such as mushrooms and zoanthids are excellent choices for beginners because they are hardy, forgiving, and adaptable to a range of conditions. Many LPS corals also do very well in desktop tanks when kept to appropriately sized specimens. The key is allowing room for growth and resisting the urge to overcrowd the tank early on.

For a full list of our recommended corals, check out our blog, "Top 7 Corals You Can Keep in a Desktop Reef Tank".

Fish in Small Reef Tanks

In tanks under 5 gallons, we recommend very small, low-activity fish. Most of our recommended fish do not have a swim bladder, meaning they perch on the sandbed or rockscape rather than swim long distances.

In big tanks with faster swimmers and more aggressive eaters, tiny gobies can get outcompeted for food or even eaten by larger tankmates. When chosen carefully, a desktop tank can provide a calmer, more controlled environment that supports their long-term success.

40oz Micro Tank (Choose 1):

• Eviota / Trimma Goby

• Green Banded Goby

• Flaming Prawn Goby

• Panda Goby

• (List Above)

1/1.5 Gallon Small-In-One (Choose 1-2):

• Neon Goby

• Red Head Goby

• Clown Goby

• (List Above)

4 Gallon Mini Pond (Choose 1-3):

• Hi Fin Goby

• (List Above)

5 Gallon Small-In-One XL (Choose 2-3):

• Watchman Goby

• Clownfish (Very small single clownfish or pair)

• Court Jester Goby

• Banggai/Pajama Cardinal

• (List Above)

Invertebrates: A Perfect Fit for Micro Reefs

Invertebrates are where small reef tanks truly shine. Snails, small hermit crabs, shrimp, and micro brittle stars add movement and interest while also performing valuable cleanup duties. Because they produce far less waste than fish, they are much easier to support in limited water volume. Inverts provide the “alive” feeling many people want from a reef tank without pushing the system beyond its limits, making them ideal residents for desktop aquariums under 5 gallons.

A few of our favorite invertebrates:

• Sexy Shrimp

• Cleaner Shrimp

• Dove Snail

• Nassarius Snail

• Cerith Snail

• Pom Pom Crab

• Blue & Red Leg Hermit

For a full list of recommended invertebrates, check out our blog, "Top 7 Invertebrates You Can Keep in a Desktop Reef Tank".

What Doesn’t Belong in a Desktop Reef

Some animals simply require more space or feeding than a micro reef can provide. Large fish, active swimmers, and heavy feeders should be avoided. These animals may survive temporarily but often struggle long term, leading to unnecessary stress or loss. Many popular saltwater aquarium fish such as tangs and wrasses are not suitable for desktop reef tanks.

Fish to Avoid:

• Wrasses

• Tangs

• Angelfish

• Seahorses (Dwarf seahorses are possible, but difficult as they require frequent, heavy feeding)

• Maroon Clownfish

• Eels

• Anthias

Why Small Tanks Work When Stocked Correctly

When livestock is chosen carefully, small reef tanks offer excellent coral growth, reduced maintenance, and a peaceful viewing experience. Fewer animals mean fewer problems, and a well-designed desktop tank can remain stable and thriving for years. Success in a micro reef comes from restraint, patience, and thoughtful selection, rather than from pushing limits.

Start Your Desktop Reef Journey

By keeping stocking simple and intentional, you’ll create a reef tank that’s easier to maintain, healthier for its inhabitants, and far more enjoyable to own. Are you ready to get started? Our Plug-N-Play Kit comes with everything you need to get your tank up and running, included 5 hand-selected, beginner-friendly coral frags from our friends at Oceanic Gardens.