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Black Cap Basslet Overview, Care, Tank Setup & More

The Black Cap Basslet is a stunning fish decked with a vivid purple body and a black diagonal cap that instantly stands out in any aquarium setting.

The care instructions for these friendly creatures are on the east side, so beginners should face no problems in adopting them. For the most part, the Black Cap Basslets are very hardy and quickly acclimate to their new surroundings.

If you’ve got plans on adopting them, make sure you check out this guide for care instructions.

Species Overview

Level of CareBeginner-friendly
TemperamentFriendly towards most tank mates except conspecifics
Appearance4 black vertical stripes against a white body
Life Expectancy2 to 4 years or more
Size3” to 4” max
Tank Size30-gallon tank
Tank EnvironmentSaltwater with spacious swimming space with lots of rock
Tank MatesGenerally peaceful with other community fish

The Black Cap Basslet’s scientific name is Gramma Melacara. They originate from the Western Central Atlantic Ocean, including the Bahamas. You’ll find them swimming near cliffs and steep drop-offs, always staying near a shelter.

Their extraordinarily bright and beautiful colors make them the primary reason why aquarists prefer to keep them in their community.

The Black Cap Basslet is the textbook definition of a beginner-friendly fish. The only bad thing about them is their small life span,

they don’t live very long, with an average life span of 2 to 3 years old. However, if you provide them with the ideal water conditions, they may live longer than three years old.

Make sure to stay consistent with water parameters and quality to help them live a long life.


The appearance of the Black Cap Basslet gives them an edge over their tank mates. Their vibrant colors are the main reason for their popularity, and you’ll find many of them in reef tanks all over the world.

Their basic pattern is pretty simple: the main body is a brilliant color that varies from purple to magenta with a diagonal jet-black color running from the dorsal fin to the lip.

The average size of a Black Cap Basslet is only 3 to 4 inches in length. The actual size depends on the quality of care provided, gender, and other factors.

It is uncommon for this fish species to hit the maximum potential size in captivity.


The maximum size of a Black Cap Basslet fish is 4 inches. The largest scientifically measured Blackcap Basslet is at 3.9 inches, rounded off to 4 inches to put things in perspective. In captivity, they’ll rarely grow beyond 3 inches.


For the most part, the Black Cap Basslet is very peaceful with its tank mates and doesn’t like to cause trouble.

They prefer to seek shelter near corals, reefs, and live rocks, which is where they’ll spend the majority of their time.

The only times when they show levels of aggression is when you introduce similar-looking species, conspecifics, and their kind.

They are slightly territorial and will get agitated if other fish swim near their home.

They spend most of their time hiding out and then swimming out to grab food when it’s time to eat. It won’t venture far out from fish territory and strive to stick as close as possible.

Because they’re not too friendly to their kind, adding only one Black Cap Basslet to the marine tank may be necessary.

Black cap basslet facing towards camera

Hiding Behavior

It is part of their normal behavior, and Black Cap Basslets will spend much of their time hiding in their preferred rock work.

They are easy to startle and will retreat into their hiding spot at the slightest hints of danger. You can encourage them to become bolder by placing bolder fish in the tank. It may encourage them to come out.

They will hide a lot when you introduce them into the tank for the very first time. Don’t worry though, they’re getting adjusted to their new environment and will become bolder after realizing they’re ‘in the clear.’ It is worth noting that each Black Cap Basslet fish has its personality, and you’ll never know how things will work out.

Perhaps they’re intimidated by larger fish in the tank, or maybe something else in the tank is scaring them – each case is its own story.

Are these Reef Safe?

Perhaps the most critical question to consider with any saltwater fish (if you plan on adding them to a reef tank) is whether they’re a threat to your reef or safe.

The good news is that the Black Cap Basslet is very reef-safe. They prefer to live in a saltwater tank with a reef and leave your corals, invertebrates, and other clams alone.

Tank Mates

Because of their non-aggressive nature, the Black Cap Basslet should get along well with other fish. Finding the ideal Black Cap Basslet tank mates should be reasonably straightforward, but you have to remember a few rules:

  • Don’t add predator fish that can swallow them whole.
  • Avoid aggressive fish like triggerfish that may decide to give your Black Cap Basslet a hard time.
  • Finally, avoid fish that make homes in rock works and crevices.

Black Cap Basslets can get pretty agitated if they feel that their territory is being infringed. It would help if you avoided fish that may look too similar to your Black Cap Basslet.

A perfect example of this is the Royal Gramma Basslet and Royal Dottyback. It will bring out their territorial instincts and cause them to go berserk – which isn’t suitable for anyone.

Black Cap Basslets will do well with small, docile species, such as the following:

  • Angelfish
  • Gobies
  • Filefish
  • Jawfish
  • Rabbitfish
  • Squirrelfish
  • Clownfish

Fish that you must avoid under all circumstances include:

  • Snappers
  • Lionfish
  • Groupers
  • Eels

You can keep your Black Cap Basslets with each other if you provide them with enough space. A small tank will provoke hostilities between them, and they’ll continuously fight each other, disrupting their stress levels.

The easiest way to avoid fighting is to mimic the natural habitat of the Black Cap Basslet, which we’ll discuss below.

Ideal Tank Conditions

The minimum Black Cap Basslet tank size is 30 gallons for one fish. It allows them to swim around and satiate their inquisitive nature comfortably.

If you decide to add two Black Cap Basslets, you should upgrade the tank size to around 60 gallons instead. As a general rule, you should aim to add another 20 gallons per fish if you don’t want to harass each other.

They’re hardy fish that can survive a range of water conditions. However, it would help if you strived to mimic their natural habitat to increase their lifespan. It is not difficult at all.

Check out the following water parameters to keep your Black Cap Basslet happy:

  • Temperature: 73 °F – 80 °F
  • pH: 8.1 – 8.4
  • Specific Gravity: 1.020 – 1.026 (1.025 is ideal)
  • Water Hardness (dKH): 8 – 11°

When you first start your tank, you should test the water every 2 to 3 days. Ensure the water composition does not change very often; you can stop trying when the water composition comes steady.

It is essential to check the water every month. It will help you know if you need to add anything to adjust the chemistry.

As a general rule, it may be essential to change the water routinely. Aim to partially change at least 20% of the water every four months.

It is necessary to keep an eye on the Black Cap Basslet during water changes. They are quick to startle and may jump out of the tank. Make sure to seal the tank with a secure lid to ensure they don’t escape.

Things to Add to the Tank

Add as many rock works as possible to make your fish feel comfortable. These are saltwater fish, after all, and prefer to hang out near corals, caves, and reefs.

It can be fun to observe them interact with corals in the tank. Live rocks will aid with biological filtration and help them quickly adjust to their new home.

Get about one pound per gallon or more of high-quality porous rock. Avoid buying base rock, which is cheaper but does little more than take up space in the tank. Make sure only to use good stone in your tank to give your fish a good time.

Some other pieces of equipment that you will have to buy include:

  • Filter
  • Heater (if applicable)
  • Air pump
  • For the substrate, you can choose a shallow sand bed, a deep sand bed, or just a bare bottom
  • Powerhead to provide water movement
  • Protein skimmer to avoid issues with algae
  • Hydrometer, preferably a refractometer for more accurate measurements

A hydrometer can be vital if you need to check the quality of water. It will help you measure the specific gravity of the tank and indicate if the water has enough tanks.

Black Cap Basslets prefer to live with dull lighting. It is recommended to add LED lights because they don’t contribute to any heat in the water. It means you won’t have to worry about uneven water temperatures all the time.

It would help if you considered adding a variety of saltwater plants that will not only make your tank look more visually appealing but make the tank look natural.

Some plants need to be adequately secured to the substrate, rockwork, or other stable surfaces to grow. If you fear it will take additional work to add saltwater plants, you can make do with artificial tanks.

We’ve rounded up our list of suitable and beginner-friendly saltwater plants that will keep your Black Cap Basslet happy:

Halimeda: Also known as the ‘money plant’ based on their unique oval-shaped leaves, Halimeda is a hardy plant that can survive in most marine tanks. They need enough light and calcium to grow abundantly. They’ll get along well with most fish in your marine tank.

Green Finger Algae: Their stunning green color makes them a welcome addition to any saltwater tank. The Green Finger Algae is compatible with most fish, including the Black Cap Basslet, and helps keep the tank healthy.

Turtle Grass Shoots: These plants require a deep sand bed (at least 6 inches) with intense lighting for 8-10 hours every day to acclimate fully. They get along well with Black Cap Basslets and become the preferred hanging spot for most of your invertebrates and small fish.

Dragon’s Tongue Algae: This beautiful plant adds a gorgeous pop of bright orange color and visual interest to your tank. It also regulates the tank’s water quality levels. Most omnivorous fish will leave them alone, except for herbivores – they’ll straight up eat the Dragon’s Tongue Algae.

Food & Diet

The Black Cap Basslet fish is a carnivorous species that prefer to eat meat and other foods that are rich in protein. Fishkeepers will feed them a diet of zooplankton and herbivores for their daily intake of fiber and other essential nutrients.

In the wild, a large portion of their natural diet consists of small marine animals and plankton. It may be difficult to replicate their exclusively carnivorous diet in captivity.

However, you can feed them in a home tank. They’re not very picky eaters once they become acclimated to their new home.

Feed them two times a day with marine origin foods and micro pellets. Only feed as much as they can eat in 2 to 3 minutes. Adding too much food to the tank could disrupt the nutrient level of the environment and elevate your stock’s stress levels.

If possible, their diet should include amphipods, copepods, isopods, and live or frozen shrimp. To meet their daily vitamin intake, you should provide them with vitamin-enriched brine shrimp. It will allow them to retain their bright purple colors and stay active in their tank.

Breeding Guidelines

Due to their beautiful colors and popularity, many fishkeepers are interested in breeding Royal Cap Basslets. If you plan on producing them, you might have an easy time. In the wild, males will make their nests using macroalgae in carefully selected regions.

You’ll have to find male and female specimens, for starters, but this won’t be easy because there is no sexual dimorphism between them. Ask your dealer to tell you which ones are males and which are females. For the most part, males are generally larger than females.

As we mentioned earlier, you should introduce pairs of Black Cap Basslets in a tank at the same time to avoid aggression levels. Make sure to add a male and female in the marine tank. You won’t have to do anything too tricky apart from mimicking their natural habitat to encourage breeding.

The male will start to build a nest over the next few days. He will use plants, rocks, and other small pieces to build the foundation of the nest. Once this is done, the female will swim over to the nest and lay her eggs (between 10 to 100 eggs). It won’t take very long, and shortly after, the male will fertilize them.

The Black Cap Basslet’s eggs are not bigger than just 1mm in diameter and should hatch in only six days in the sequence they were laid.

During this time, both parents will stand guard and viciously defend their eggs from any fish they perceive to be a threat.

The newly hatched should start feeding on s-type rotifers within 14 hours. The good news is that their fry is relatively easy to care for. To increase their chances of survival, you will have to remove any fish that may consider them to be prey.

Black Cap Basslet Care: Dangers and Diseases

Despite being a hardy species, the Black Cap Basslet does fall pretty to parasites and common saltwater diseases, including Marine Ich, Velvet, and HITH.

In most cases, prevention is better than cure, and you can avoid infections by merely keeping the tank in good condition.

Before adding anything new to the tank, you should quarantine it for at least two months to ensure it doesn’t have any parasites or diseases.

Where to Buy?

A Blackcap Basslet for sale can be purchased from any aquarium store near you, online stores, and online forums.

However, prices may depend on your location and the availability of the fish. In most cases, the Black Cap Basslet price varies from $40 to $130 or more, depending on its age, size, and health.

Wrapping Up

The interest in Black Cap Basslets is picking up steam for obvious reasons – they’re beautiful, reasonably low-maintenance, and thoroughly entertaining to observe.

The only downside to them is that they don’t live very long: the average Black Cap Basslet lifespan is only 2 to 4 years, and if you don’t meet their required tank conditions, it could plummet.

We hope this guide on Black Cap Basslets proved to be helpful. We’ll keep adding more techniques and improvements to this guide as we become aware of them with time.

If you’ve got any suggestions on things we should improve upon or add, we’d love to know.