Photo Credit: Haplochromis (CC License)
If you’re a beginner, I wholeheartedly recommend against having a 10-gallon saltwater tank. Small tanks seem easy to maintain at first glance, but little does one know they’re downright treacherous.
A 10-gallon tank’s dimensions are 20” x 10” x 12” (50.8cm x 25.4cm x 30.5cm).
When empty, it weighs only about 11 lbs. And when filled with water, the weight increases by almost 9 times – reaching 99 lbs.
Down the road, we will discuss the vices of a 10-gallon tank. However, it doesn’t mean it’s impossible to keep nano saltwater tanks. If you have a fair share of experience in the saltwater hobby, there are several stocking options to choose from.
The four critical characteristics you should look for when choosing saltwater fish for a small tank are:
- Small size (4 inches or less when fully mature)
- Peaceful temperament
- Habitat in the wild is a small piece of reef
- Slow swimmers or ones that perch on the rock
Let the fun begin!
15 saltwater fish suitable for a 10-gallon tank are:
Our Pick Of Saltwater Fish For 10-Gallon Tank
- Clown goby
- White banded possum wrasse
- Tailspot blenny
- Chalk bass
- Helfrichi firefish
- Yellow watchman goby
- Royal gramma
- Neon goby
- Catalina goby
- Blue chromis
- Dwarf seahorse
- Fire Dartfish
- Purple firefish
- Blue-green chromis
- Hector’s goby
A clown goby’s maximum length is 1.5 inches, making it a perfect addition to a 10-gallon tank. These lively creatures love to jump around and perch on rocks and corals.
Their brilliant yellow colors and playful and curious personalities instantly add beauty and character to any tank. They love to freely hover and parade along the water column.
Also, don’t forget that they’re completely reef-friendly. So you need not worry about your corals getting wrecked.
These fish are known to get competitive and territorial when kept with their own kind but get along reasonably well with other species. Therefore, it’s recommended to keep only one clown goby per tank.
You can give them brine shrimp, mysis shrimp, and other frozen (and thawed) food. They’re not picky about what they put in their mouth.
Bottom line: You can’t really go wrong with clown goby if you’re a beginner.
White Banded Possum Wrasse
Growing only around 3 inches long, white banded possum wrasse make stunning additions to any nano tank, thanks to their attractive black and red stripes and spots.
These are peaceful wrasses that don’t really bother any other creature in the tank, be it corals, invertebrates, or other fish.
But since they love to jump around, you better have a sturdy canopy installed to prevent them from jumping to death.
Like most wrasses, the white banded possum wrasse is a micro-carnivore that primarily snacks on live rock-inhabiting worms and crustaceans in addition to aquarium foods.
In the tank, you can give them flake food, mysis shrimp, and cyclops-eeze.
And since they are pretty peaceful and solitary, there’s a good chance they get bullied by assertive tankmates. Therefore, you should choose the other inhabitants of the tank carefully.
Tailspot blenny is the smallest of its kind – therefore, they are perfectly suited for 10-gallon fish tanks.
At max, these fish clock in around 2.5 inches long – making them an excellent choice for just about any tank size, whether it’s nano, pico, or full-sized reef tank.
Docile and friendly, tailspot blennies come in various colors like orange, blue, white, and black. But the feature that stands out most is the brilliant black and orange band positioned right below the eyes.
Tailspot blennies are pretty popular among aquarists since they’re easy to take care of and are quite entertaining.
Just like the majority of saltwater fish present on the list, these fish are carnivores that thrive the best in tanks with several live rocks.
Helfrichi firefish are the smallest kind of firefish to exist. At max, they only grow around 2.5 inches long. Therefore, they make a great stocking choice for a 10-gallon tank.
Also known as helfrichi’s dartfish, these fish sport a distinctly yellow head and a purple forehead.
Their bodies come in mixed shades of lavender, white and green. Their vibrant colors make them super entertaining to watch as they hover along the water column.
Helfrichi firefish often prefer using caves and rocks as shelter and mainly feed on finely chopped krill, fish roe, and red plankton.
Since these fish cannot eat from the water surface, you need to offer them food that sinks or place their food in midwater.
Like the rest of the firefish species, helfrichis are jumpers. Therefore, you need to put on a tight lid, so they don’t jump out of the tank.
Also, since they are inherently shy creatures, you need to be mindful of the tankmates you choose for them.
When cornered, these fish tend to jump out of the tank through small openings.
Chalk bass are hardy little fish that don’t require any extra care beyond standard reef requirements. At max, these fish grow around 4 inches long.
Thanks to their unique colors and peaceful temperament, chalk bass tick all the right boxes when it comes to selecting a suitable fish meant for small tanks.
As you already know, chalk bass have a super unique appearance, thanks to their brilliant colors like blue and orange.
These fish camouflage in the wild. Therefore, they can change colors quickly depending on the surrounding lights.
And since they’re pretty reserved, you need to ensure that there is plenty of hiding space in the tank in the form of plants and live rocks.
In addition to a carnivore diet, these fish need to be fed pigment-enhancing food to maintain their dazzling coloration. To fulfill protein needs, you can give finely chopped squid and krill.
Yellow Watchman Goby
Yellow watchman gobies are definitely the most famous gobies out there. Growing around 4 inches long, these fish are mainly known for their unique lips that make them look as if they’re frowning all the time.
The blue spots across its face are equally iconic too.
Also known as yellow prawn or yellow shrimp goby, these fish share a symbiotic relationship with snapping shrimps, who clean up after the goby is done eating.
Although these gobies are peaceful for the most part, they are also jumpy. Thus, installing a tight-fitting lid is a good idea to stop them from escaping.
They mostly stay at the bottom and don’t prefer strong currents. Therefore, you need to ensure enough burrow room with lots of sand and coral rubble on the bottom.
It’s also best not to keep two male yellow watchman gobies together since it can result in unsolicited aggression.
And interestingly, although named yellow watchman goby, these fish come in a variety of colors like gray, brown, and orange.
A nano fish with dazzling colors? Sounds like the perfect fit for a 10-gallon saltwater tank. Growing only around 3 inches long, it is a must-have fish if you’re looking for a pop of color in the tank.
The upper half of the body is purple, and the lower half is bright yellow. Around the mid-section, there’s an orange gradient, making the fish look like it came straight out of a coloring book.
Temperament-wise, these fish are peaceful for the most part. However, owing to their shy demeanor, they require ample rockwork, including caves, reefs, and coral outcroppings.
And by the way, they don’t really make active swimmers. They just love to burrow.
If your royal gramma is a captive-bred specimen, you can feed it prepared pellets and flake food. But make sure to occasionally provide carnivore food as they would have had it in the wild.
Growing around 1.2 to 1.4 inches long on average, neon goby is a vibrant little addition to any saltwater tank, thanks to the striking neon blue line running along its body.
Neon gobies are cleaner fish that love gently nibbling on other fish, cleaning their bodies from dirt and algae.
These fish do great in community tanks since they are friendly and peaceful.
In the wild, gobies usually scavenge for food. But there’s a good chance there’s not enough leftover food in a tank as small as 10 gallons. Therefore, you need to supplement their diet with meaty and high-protein foods like finely chopped shrimp.
Blue chromis is a favorite among saltwater enthusiasts due to its brilliant blue colors and lively personality. These fish grow to a maximum length of 4 inches and are super peaceful and hardy – making it a treat to raise them.
You can keep a pair of blue chromis in a 10-gallon tank. Some may argue that you can add up to 3, but you’d be really pushing it.
Temperament-wise, blue chromis are peaceful and love to stay out of skirmishes. And when kept in groups, they almost always have a pecking order, leading to animosity and fights in the tank.
Therefore, don’t add too many of these fish to a small tank.
Purple firefish are known by several other names like fire goby and decorated firefish.
Growing to a maximum size of 4 inches, these multicolored fish have a purple face, a yellow or white body, colorful caudal fin, and red or orange fins.
Disease-resistant, hardy, and easy to feed, we can easily see why these fish are so popular among saltwater enthusiasts. But also note that these are among the most aggressive ones from the firefish family.
Therefore, I would suggest against keeping more than one purple firefish in the same tank. And since these fish are shy and reclusive, they need plenty of hiding places like shelters and caves.
If you were hoping that our beloved clownfish would make the cut, I’m really sorry to disappoint you. But unfortunately, contrary to popular belief, these fish don’t belong in nano tanks.
Even the smallest or most docile clownfish requires at least 20 gallons of space for a single fish to lead a comfortable life.
So, if you’re interested to read up more on how many gallons do different clownfish species need, here’s the article you’ll love:
So, that’s a wrap for our roundup of the best saltwater fish for a 10-gallon tank.
Next, here’s a list of suitable invertebrates for a 10-gallon tank:
- Sexy shrimp
- Small hermit crab
- Peppermint shrimp
Sexy shrimps only grow around0.8 inches long. Thus, you can easily keep a group of these shrimps in a 10-gallon tank.
Sexy shrimps don’t just look attractive but also have great personalities. But note that you shouldn’t keep them with carnivore fish as they’re so small that they can easily get snacked on.
Small Hermit Crab
Small hermit crabs range in size from ½ inch to 4 inches. You can add a couple of them to a 10-gallon tank.
Despite their petite size, these crabs are bold – thus, they prefer exploring uncharted territories, have quick reflexes, and have an affinity for investigation.
In the wild, they snack on parasites found in other fish. But in captivity, you need to feed them a carnivorous diet.
Peppermint shrimp grow about 2 inches long at max. Therefore, you can keep a number of them in a 10-gallon tank.
The shrimp’s moniker comes from the red stripes that run the length of its transparent to cream-colored body.
These are docile, peaceful shrimps that can get somewhat territorial at times!
And here’s a list of suitable corals for a 10-gallon tank:
- Green Star Polyps
These are small polyp corals that come in an array of incredibly vivid colors like purple, pink, blue, and green.
Zoanthid corals are often recommended to new marine aquarium owners since they are relatively easy to raise.
Mushrooms are yet another highly hardy corals that come in somewhat drab to compelling variations. These are hardy, easy to raise, and require low maintenance.
Under the right conditions, mushroom corals can grow quite rapidly.
Green Star Polyps
Green star polyps are beautiful little flower-like polyps that grow prolifically under the right circumstances in a reef aquarium.
These corals grow fast and hardy. Therefore, they’re often heralded as the best starting coral for beginners.
Now, let’s move on to another fun segment where I pool in all the relevant answers on the query from different platforms so you can view them all at once.
Saltwater Fish For 10-Gallon Tank | Real Answers By Real People
Note: All the answers expressed below purely belong to the respective authors.
“In my opinion, red spotted gobies make a great choice since they’re pretty, reef-safe, and stay small even as adults.”
“A pair of clowns will eventually get too aggressive in a 10-gallon tank. So I’d stick to smaller, peaceful fish like firefish, small gobies, and blennies.”
“My suggestions would include tailspot blenny, barnacle blenny, combtooth blenny, shrimp goby, cleaner goby, pink-streaked wrasse, possum wrasse, and geometric pygmy hawkfish. Not all of them together, of course.”
“In a tank that size, I would go with a pair of hi fin red-banded gobies with a cane pistol shrimp. Also maybe 1 azure damsel.”
“You might want to look at a Pederson’s cleaner shrimp as they stay small even as adults.”
“In a 10-gallon tank, my top picks would include tailspot blenny, a small goby, and a possum or pink-streaked wrasse.”
Now, let’s look at all the stuff you need to get a 10-gallon tank up and running!
What Do I Need For A 10-Gallon Saltwater Tank? 10-Gallon Saltwater Tank Setup?
A 10-gallon tank does have more than one Achilles’ heel. But the best thing about small tanks is that all the equipment and maintenance costs are way cheaper than what’s required for a big tank.
Here’s a list of everything you need to get a 10-gallon tank up and running:
- A 10-gallon fish tank
- LED Light
- Light Controller
- Aquarium Heater
- Auto Top Off
- Protein Skimmer
- Flow Nozzle
If you are aiming for a fish only with a live rock (FOWLR) setup, the aforementioned list should cover you well.
But if you are planning to add corals, you will want to tweak a few of these and add other items to meet specific needs. For instance, an aquarium controller like Neptune Apex and dosing pumps can be super helpful, although a little expensive.
Be Mindful About The Nitrogen Cycle
If you’re new to the hobby, you wouldn’t want to miss out on reading up on the nitrogen cycle. So I’ll quickly explain what it is as simply as possible.
A tank needs to establish a proper nitrogen cycle before adding any pet inside. The nitrogen cycle refers to breaking down the biological matter of the tank via bacteria.
First, certain bacteria break organic matter into ammonia. Second, another type of bacteria breaks ammonia into nitrite. Third, other bacteria break nitrite into nitrate. And finally, other bacteria break nitrate into nitrogen that bubbles out of the tank.
The Risks Of A 10-Gallon Saltwater Tank
I said small tanks are treacherous above. Now, I’ll tell you why.
- Small tanks offer no room for errors. If you overdose your tank with certain medications, there’s every chance you may kill fish and the reefs.
- Toxic buildup of harmful compounds like ammonia, nitrate, and nitrite happens fast – just over a couple of days. So you will constantly have to be on your toes to see if the parameters have risen above the safety levels.
- Small tanks directly translate to space scarcity. And as primitive as we think fish are, they’re all territorial when it comes to sharing space or resources. So, when there’s a lack of space, your fish will experience undue stress, which in turn suppresses their appetite and lowers their immunity.
- Temperature fluctuation happens fast and often in small tanks. A slight change in one corner can be felt throughout the tank in no time. And no matter how hardy a fish is, it doesn’t react too well to sudden temperature changes.
Frequently Asked Questions
How Many Clownfish Can I Put In A 10-gallon tank?
Unfortunately, you can keep 0 clownfish in a 10-gallon tank.
I’d say the minimum recommended tank size for a single clownfish is 20 gallons. However, it’s not at all uncommon to see clownfish being subjected to a 10-gallon tank.
I’d only recommend doing so if you have a fair share of experience with smaller tanks.
How Many Fish In A 10-Gallon Saltwater Tank?
At best, you can only keep 1-2 fish in a 10-gallon tank. That’s because you’ll also need to allocate some space for a cleanup crew that includes shrimps and snails.
When choosing saltwater fish for a 10-gallon tank, your options aren’t limited. As a matter of fact, there are so many great choices to choose from, like clown gobies, blue chromis, chalk bass, royal gramma, and tailspot blenny.
However, a saltwater tank that small is tricky to maintain. The parameters will inherently become volatile. Therefore, if possible, opt for a bigger tank. Both you and your fish will be happier.