It can be very tempting to choose an inexpensive fish, like the yellowtail damsel, for your first saltwater aquarium. You definitely don’t want to risk losing a more expensive fish, and there seem to be plenty of damselfish to go around.
The problem is that yellowtail damsels are much more aggressive than other species of marine fish, leaving future tanks empty or broken down because of compatibility issues.
Yellowtail damsels have beautiful colors and are extremely hardy, but this attractive fish species can’t be kept by all hobbyists.
Keep reading to learn everything you need to know about yellowtail damsels and how to keep one of these common saltwater aquarium fish in your home setup!
Chrysiptera parasema is commonly known as the yellowtail damselfish, usually shortened to the yellowtail damsel; they may also be known as goldtail demoiselle, though this is less common.
These beautiful fish are part of the Pomacentridae family of damselfish and clownfish and resemble many other species within this category.
Yellowtail damsels are native to the warm tropical waters of the western Pacific Ocean. They can be found in the coastal waters of several countries, including the Philippines and Papua New Guinea.
Unlike some of the most famous fish in the aquarium hobby, yellowtail damsels are rarely, if ever, found around the Great Barrier Reef off the coast of Australia.
Instead, this common fish species sticks to sheltered inshore reefs with lots of coral, especially small polyp stony (SPS) corals like Acropora. There, they can be found cohabitating in small groups.
The yellowtail damselfish is aptly named for its yellow caudal fin. These fish are a brilliant blue apart from their signature tail.
Yellowtail damsels are especially popular saltwater fish among beginner fish keepers because of their inexpensive price and small size; these fish only grow to be about 2.5-3.0 inches long (6.4-7.6 cm) at adult size, which can be appealing to hobbyists who might be used to smaller, freshwater species.
Though small, you should not underestimate these hardy fish! As we’ll discuss later, they have very bold personalities and can quickly overrun an aquarium.
You should note that yellowtail damsels are sometimes mistaken for the azure or blue damsel (Chrysiptera hemicyanea). Side by side, these fish look entirely different. But it can be easy for the untrained eye to make this mistake.
Both yellowtail damsels and azure damsels are pretty much the same blue color combination with yellow accents. The difference is that yellowtails only have the yellow color on their tail while azures have yellow extending from their caudal fin to their underbelly.
If you do happen to end up with an azure damselfish instead, it’s not the end of the world. In fact, azure damsels tend to be less aggressive than yellowtails, so this mistake could be favorable in the end.
How long do yellowtail damsels live?
Like most other marine fish, yellowtail damsels can live a surprisingly long time.
These fish are incredibly hardy and can adapt to most environments and changes in conditions. Because of this, it is estimated that they can have a life cycle of up to 15 years in pristine aquariums.
While it’s much more likely that your fish only lives to be about five years old, there’s always the possibility that they surpass that one-decade mark.
Male vs. female
As aggressive as they are, yellowtail damsels are relatively easy to get to form pairs in the home aquarium. However, it can be pretty tricky to tell the males apart from the females.
As a type of damselfish, yellowtails can change sex as they mature, much as clownfish do.
The main difference between male and female yellowtail damsels seems to be the size; male yellowtails can be slightly larger than female fish, though this can be difficult to see and might not always be accurate.
If you want to breed yellowtail damsels, it would be best to purchase an already formed pair or buy a group and let them pair off on their own.
Yellowtail damsel tank requirements
Apart from their simple yet eye-catching coloration, one of the most appealing things about yellowtail damsels is their low care requirements.
It is true that these fish don’t need very much space, and a minimum 20-gallon tank size (75. 7 L) is more than enough space to accommodate one yellowtail damsel as the only fish in the aquarium.
Keeping one yellowtail damselfish with another fish in this size aquarium is possible as long as temperaments match.
It is recommended to start with a larger aquarium to give tank inhabitants as much space as possible, especially the more aggressive ones.
Otherwise, yellowtails need stable aquarium water parameters with a constant temperature of 72-82° F (22.2-27.8° C).
Salinity should also be constant between 1.020-1.025. As these are saltwater fish, they need a higher pH level than freshwater species, between 8.0-8.4.
As for the actual tank setup, these fish can happily be kept in a larger fish only (FO), fish only with live rock (FOWLR), or full community reef tank setup. As we’ll discuss later, these fish tend to take over and control specific portions of the tank and don’t need much room to swim.
Are yellowtail damsels suitable for beginners?
Often, many aggressive damsel species will be displayed in large groups in a single tank in the aquarium store.
They immediately catch the eye with their beautiful colors and relatively low prices.
The problem is that while yellowtail damsels are one of the hardiest and most forgiving species of saltwater fish available in the trade, they aren’t the best for a beginner fish tank due to their extreme aggression, which can quickly deter beginner aquarium keepers from progressing in the hobby.
Yellowtail damsel tank mates
The truth is that yellowtail damsels can be kept with most other reef-safe fish, including tangs, angelfish, wrasses, and other damsels, like clownfish.
Some hobbyists even choose to create damsel-only fish tanks, featuring other species like the azure damsel (Chrysiptera hemicyanea), domino damsel (Dascyllus trimaculatus), and starcki damsel (Chrysiptera starcki).
Some hobbyists have had luck keeping larger groups of damsels together along with other marine species in larger tanks.
The trick to these combinations is understanding how damsels behave and interact with other compatible fishes and then stocking them accordingly. Avoid predatory fish that might make a meal of your precious pet.
The first step to having a successful damsel tank is planning out the order of the livestock being added. In most cases, damsels should be added last so that other fish have time to establish their territories and pecking orders.
Some hobbyists have found that adding more species of the same kind of damsel can help mitigate aggression. Some common damselfish species are also naturally more aggressive than others, so minor details like that are also important to consider.
Keep in mind that even if you have added your fish in the correct order and diffused aggression as much as possible, there is still the possibility that your damsel takes over the tank and makes it unbearable for all other inhabitants.
On the flip side, it’s possible to get a model citizen, with your yellowtail damselfish welcoming and respecting everyone else in the aquarium.
Can yellowtail damsels live with clownfish?
In most cases, yellowtail damsels can peacefully live with clownfish.
Of course, there have been stories of damsels killing clownfish overnight, but the majority seem to stick to their respective territories within the tank.
Yellowtail damsel behavior
So what exactly makes the yellowtail damselfish a difficult fish to keep?
From a distance, this species is the perfect fish for a beginner saltwater fish hobbyist: they’re incredibly hardy, colorful, and stay small. The problem is that their attitude is nowhere near as small as they are.
Yellowtail damsels are bullies and aggressive tank mates, through and through. They will set up a decently large territory in the tank and defend it with their life.
These fish generally have no mercy, though some hobbyists get lucky and have well-behaved ones. For the most part, though, these fish will fin nip and chase until the receiving fish can’t handle it anymore.
Do damsels kill other fish?
Yes, yellowtail damsels have been known to kill fish, especially if the other fish is smaller and less aggressive than the damsel, which most coral reef fish are.
To keep this from happening, we recommended rehoming the aggressive fish. Some hobbyists even use their sumps and refugiums or a separate tank to house particularly aggressive damsels if they can’t immediately rehome them.
The other option includes adding more damsels, which could potentially decrease aggression, though this is not guaranteed.
What is the least aggressive damselfish?
There are many different species of damsel. Surprisingly, yellowtail damsels and other species from the Chrysipteragenus are thought to be some of the less aggressive ones.
Some of the more peaceful damsels are:
- Azure damselfish (Chrysiptera hemicyanea)
- Springer damselfish (Chrysiptera springeri)
- Talbot’s damselfish (Chrysiptera talboti)
Of course, personality will depend on each individual. However, most hobbyists tend to have the best luck with these more peaceful damselfish species.
Yellowtail damsel diet
In addition to easily acclimating to new water parameters, yellowtail damsels will eat all fish foods. They are mainly omnivores, but they will readily accept and appreciate any meaty food, like brine shrimp, thrown into the tank.
For the most part, a high-quality marine flake or pellet food can compromise the majority of their diet. Yellowtail damsels will also happily accept a varied diet with live, frozen, and freeze-dried options.
Yellowtail damsels are the perfect fish for beginner marine aquarists, but only in theory. These can be awfully territorial and aggressive saltwater fish, making for frustrating compatibility issues in the reef aquarium setup.
Otherwise, they don’t need much to be happy and will tolerate common saltwater tank-keeping mistakes.
If you have any questions about the yellowtail damselfish, other hardy species of damsel, or if you have had personal experience with a particularly mean damsel, don’t hesitate to leave a comment below!