Royal Gramma 101: Care, Compatibility, Lifespan & More

The royal gramma aka fairy basslet is one of our absolute favorite saltwater aquarium fish out there. They’re easy to care for, mellow in temperament, and look beautiful.

Due to the stunning colors on this fish, they’re extremely popular in the saltwater aquarist community. They’ll stand out in your tank no matter what other fish you keep them with!

But with so many people flocking to buy these fish, there is misinformation that gets passed around. And no matter how simple royal gramma care is, you can mess things up if you don’t have the right information.

In this guide, we’ll cover everything you need to know about the royal gramma basslet. How to care for them, their lifespan, compatibility, and more!

Species Summary

Royal grammas (gramma loreto) are a saltwater fish from the Grammatidae family. They’re found mainly in the tropical Atlantic Ocean. This area spreads from the South American coast all the way up through the Caribbean, Gulf of Mexico, Florida, and ends near Bermuda.

While they cover quite a large span in their natural habitat, fairy basslets are primarily known by those in the aquarist community. The main reason for this is their extremely bright and beautiful colors.

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They’re pretty much the textbook fish for why people get into saltwater fishkeeping in the first place!

The royal gramma is also extremely easy to care for due to their hardy and peaceful nature. This makes them great for new aquarists who might be setting up their very first saltwater tank.

Royal Gramma Lifespan

The average royal gramma lifespan is around 5-6 years. We have heard from owners who have reported lifespans up to 10, but those can’t be verified.

Even though these fish are rather hardy you can still shorten their lifespan by giving them poor care. Make sure you stay consistent with water parameters and quality to help them live as long as possible.


The appearance of a royal gramma is really where these fish stand out the most. Their vibrant colors are easily the main reason for their popularity, and why you’ll find them in so many reef tanks all over the world.

Royal gramma swimming in a reef tank

They don’t have a whole lot going on in terms of patterns, it’s really all about the color with these fish. Their front half is a rich bright purple, and their back half is bright yellow. The transition point between these two colors is fairly stark, although some fish have more of a gradient midpoint than others.

Their ventral fins also match the purple coloring on the front half of their body.

At the top front edge of their dorsal fin, you’ll see a black dot about the size of their eye. This is more circular on some fish than others, but it’s always there.

Royal grammas also typically have a dark line that runs from their mouths and through the middle of their eyes. This is not always very obvious and the darkness can vary based on a number of factors including gender.

Their bodies are long with average width and taper down toward the back. They kind of look like colorful torpedoes! Their dorsal fin starts at the same point down their body as their ventral fins and bows a bit toward the middle.

Author Note: When they swim their fins tuck back quite a bit. So much that it’s kind of curious how they generate such speed!


The average size of a royal gramma is 3-4 inches in length. This can vary depending on genetics, quality of care, and gender.

It’s also rather uncommon for this fish to hit maximum potential size in captivity. 

Royal Gramma Care

Royal gramma care is not very challenging due to the resiliency and hardy nature of this fish. With that being said, you still need to have a strong grasp of the basics in order to help them live long and happy lives.

Tank Size

The minimum royal gramma tank size is 30 gallons for one fish. This will give them enough room to swim comfortably and enjoy a variety of reefs and hiding places.

If you have two royal grammas you should up this tank size to around 50-60 gallons instead. After that, aim for adding another 20 gallons per fish if you intend on keeping a bunch of them together.

Water Parameters

Royal grammas are hardy fish that can thrive in a range of water conditions. However, there is still a sweet spot that you should go for. This will increase the quality of their lives and potentially lengthen their lifespan.

Side profile of a fairy basslet

Every one of the aquarists we’ve heard from who have royal grammas pushing the upper limits of their lifespan has one thing in common, they’re obsessed with water quality and parameters. If you want to be a great owner, you should do the same.

  • Water temperature: 72°F-80°F
  • pH levels: 8.1 to 8.4
  • Carbonate hardness: 8°-12° dKH
  • Specific Gravity: 1.020-1.025

Make sure you’re performing regular water level tests to ensure that your water is in good shape. These tests will help you catch any unwanted fluctuations before they become a problem.

What To Put In Their Tank

Due to their peaceful and shy nature, you’ll want to make sure that there are a handful of places for your royal gramma basslet to hide. If they don’t have this available to them they’ll be prone to stress which can have a significant impact on their health.

Rockwork is essential

Since we’re dealing with a saltwater tank that means coral, reefs, and caves are all great choices to help this fish feel comfortable. They will likely find a specific crevasse where they spend most of their time.

It can be very fun to observe them navigating any rockwork you have in the tank. They’re very sneaky with their movements and it can sometimes feel like they’re playing peek a boo with you!

Author Note: If you’re planning on keeping more than one fairy basslets in the same tank you should make sure there’s enough space for each to call home. A large tank with one small coral feature is just as bad as a tiny tank that’s packed full of rockwork.

Common/Potential Diseases

There aren’t any species-specific diseases or illnesses you need to look out for with royal grammas. They’re very hardy and resilient fish.

That doesn’t mean they can’t get any of the common ailments that affect saltwater fish of course, but most of those can be prevented by maintaining good water quality.

Food & Diet

The ideal royal gramma diet will contain a mixture of plant and protein-rich foods. Their natural diet as a carnivore consists mostly of various kinds of live plankton, but that’s something you can’t replicate easily in a home reef aquarium.

The primary base of their diet when kept as a pet will probably come from pellet, flake, and frozen food. This will cover a lot of their core nutritional needs in an affordable and convenient way.

In addition to this, you’ll also want to add some variety to their diet by giving them some protein-rich treats a couple of times each week. Frozen or dried plankton, brine shrimp, Mysis shrimp, crustacean flesh or bloodworms are all great choices.

This mix of food will provide your fish with a balanced diet but also give them some enrichment as well. Fish enjoy treats just like people do!

Make sure you don’t overfeed your royal gramma though. Give them an average amount of food and feed them 2-4 times per day depending on your schedule. If you notice that food isn’t getting eaten adjust the quantity accordingly.

Behavior & Temperament

Royal grammas are very mellow and peaceful fish. They don’t want to cause trouble and will always seek out the protection of coral, reefs, and rocks as their default place to be.

The only situation where you might see some aggression come out is when it comes to their preferred home or hiding place. Royal grammas view these areas as their home and if another fish starts getting too nosy they’ll do what they can to discourage them.

These fish will usually spend a good amount of time hiding out and then darting out to snag food when it’s time to eat. They won’t venture to the top or bottom third of your tank very often, instead preferring to operate as close to their home as possible.

Sometimes you’ll see your royal gramma swimming upside down along rocks and other surfaces. While this might seem strange at first, it’s completely normal. It’s their way of navigating these objects, and who are we to tell them they’re wrong!

Author Note: You’ll want to make sure to have a strong lid when keeping these fish. They’re known to be quite prolific jumpers and will test their escape plan more than once.

Royal Gramma Compatibility & Tank Mates

One thing that makes royal gramma care so simple is how compatible they are with other fish. Their calm and patient temperament is perfect if you plan on keeping them with tank mates of another species.

Angelfish, gobies, hawkfish, boxfish, blue green chromis, and clownfish are all compatible with royal grammas. The list goes on and on, so we’re not going to live every single species for sanity’s sake.

But there are some things you’ll want to avoid.

Fish that are significantly larger or more aggressive than royal grammas do not make good tank mates. If they don’t harm your fairy basslet, they will scare them and increase their stress levels. This will lead to your fish being scared to leave their homes to get food which is a serious problem.

Some fish like this to avoid are:

  • Snappers
  • Lionfish
  • Eels
  • Groupers

Any fish that like to make homes in rockwork and crevices could cause a problem as well. Royal grammas can get feisty if they feel like their territory is being invaded. Even if other fish don’t mean any harm, this could be misinterpreted. 

You’ll also want to be aware of their coloration when thinking about compatibility.

Fish that look similar to your royal gramma can be a recipe for disaster. A perfect example of this are royal dottybacks. The reason for this is simple: it might make your royal gramma basslet feel territorial (or vice versa).

Compatibility With Each Other

Keeping royal gramma together is absolutely possible as long as you have enough space. These fish can be testy with each other if they have their eyes on the same place to call home.

The easiest way to avoid this is by following the recommended tank size guidelines which we listed above. That will ensure that there are plenty of hiding spots and room to swim for everyone.

Males are also more likely to pick on each other than females. This should be kept in mind when planning out your tank.

As long as you give them enough room and are mindful of gender, these fish are very compatible with each other.


Due to their beautiful colors and popularity, many people are interested in breeding royal grammas. If you’re one of them, you’re in luck!

Breeding royal grammas is very simple and is something that anyone can do (very little experience is needed).

You’ll need to have a male and a female in a standard tank. There isn’t anything special you need to do with their habitat to encourage breeding.

A nest will be built by the male over the period of a day or two. He will use rocks and various pieces of vegetation as the foundation of the nest.

Once this is finished the female will swim over to the next add her eggs to the nest. This doesn’t take very long and shortly after this happens the male will fertilize them.

It shouldn’t take more than a week for the eggs to hatch. From there all you have to do is feed them and help the little ones grow!

Now It’s Up To You

The interest in royal grammas isn’t going away anytime soon. They’re beautiful, easy to care for, and fun to observe!

We hope that this guide on royal gramma care will help you decide if this is a fish you want to keep or improve the level of care you’re giving a fish you currently own.

With more and more techniques and improvements to fishkeeping coming out each and every year, this guide is a resource that we’ll be committed to improving as time goes on. If you have any suggestions on things we should add or improve on please let us know!

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