Tag: ReefKeeping

Looking for a Triggerfish for your saltwater aquarium? Reef Triggerfish are some of the most entertaining and rewarding fish to own. I’ve personally had a great experience with a blue throat triggerfish in a mixed reef tank. Next to a scribbled rabbitfish that I had, it was my favorite fish I’ve ever owned.

I want to share this experience with you as I feel these are special fish, when you can house them in the right environment. I’ll walk you through the 8 best reef triggerfish for aquariums, most that will work in reef tanks and 2 to avoid. So let’s get started!

Introduction To Triggerfish

Triggerfish are some of the most interesting fish in the marine aquarium hobby due to their decorated appearances and incredibly bold personalities. Though these fish are full of character and can have beautiful colors, many triggerfish are not reef-safe, which prevents a lot of aquarists from attempting to keep them.

What Are They?

Triggerfish belong to the Balistidae family which only contains about 40 different species of triggerfish, already limiting the short supply of these fish that are available in the aquarium hobby.

Like many other marine fishes, most reef triggerfish originate from the lush coral reefs of the Indo-Pacific. Unlike other species, most triggerfish do not cohabitate with other reef-inhabitants and usually depend on invertebrates and corals for food rather than shelter.

These reef triggerfish are mean, hungry, fast, and strong. Hobbyists typically only keep them in predatory setups or species-only displays where there is no risk to other fish or reef invertebrates. Over the years, though, aquarists have experimented with keeping triggerfish in the reef setting to some surprising success.

Before we get into the best reef safe triggerfish for the aquarium, we need to first understand what makes the better majority of these fish not safe for the reef.

Behavior

Most species of reef triggerfish grow to a large size. This, in addition to their muscular beaked mouths and strong bodies, makes them a formidable predator for their natural prey of various invertebrates.

Interestingly, these fish are named after one of the behaviors. Though a predator, triggerfish can easily scare. When this happens, they take refuge in the rocks and use their first and second dorsal spines as a way to secure themselves. At this point, they can only be removed if that large dorsal spine is forcibly relaxed or the threat diminishes. This action resembles the pulling of a gun trigger, giving them their name.

This behavior is also observed while the fish is resting. Attempting to remove the triggerfish from its position during this time can cause injury to the fish. Because of this, transferring a triggerfish from one tank to another can take a lot of time and patience. Hobbyists usually end up having to transfer some rock along with the fish as well.

In the reef aquarium, the chances of being attacked are certainly less but never completely gone. Triggerfish will greedily splash, spit, and chomp at the surface of the water during feeding times, making the difference between a finger and the food almost indistinguishable; this behavior is known as hydraulic jetting and is usually used for uncovering and overturning prey. For these reasons, it is recommended to keep all hands out of the tank and to use tongs when feeding.

More importantly, hobbyists need to be aware of triggerfish biting at aquarium heaters and other equipment in the tank, including electrical cords. If these fish can bite through fingers, they can certainly bite through plastic!

To prevent this, it’s strongly recommended to keep as much equipment as possible in a sump or other external filtration. If this is not possible, equipment will need to be safeguarded with egg crate or other hard plastic. A titanium heater will also be able to withstand the powerful jaws of your fish!

Acrylic vs Glass Reef Aquariums

Something you need to think about before you even consider getting a reef triggerfish is the material that your aquarium is made from.

Many larger aquariums are made from acrylic because it tends to be a stronger material than glass. Acrylic also gives a noticeably sharper and clearer look into the tank, allowing you to fully appreciate the colors of your fish and corals.

However, acrylic scratches very easily. If you happen to get a triggerfish that likes biting the glass or begging for food at the surface, there is a small chance that it could end up scratching the acrylic. This isn’t a huge concern for most hobbyists, but the possibility is there and should be considered.

Diet

Apart from their aggression, triggerfish are extremely hardy and can adapt to most aquarium conditions. They will need to be fed a varied diet of hard, often live, foods that help keep their beaks trimmed.

Triggerfish need to be fed often. They are highly active and need to restore those nutrients through small feedings throughout the day; most hobbyists aim for at least 5 small portions every day.

Because of this, many triggerfish keepers set up a snail culture. This allows them to have a near-constant supply of food that also helps keep beaks trimmed. This is even better than buying from the store in terms of expense and having control over the health of the snail population. Other hard-shelled invertebrates, like clams and shrimp, may also be supplemented.

In addition to these hard foods, triggerfish will accept most frozen foods. As omnivores, they will also accept marine algae snacks.

Reef-Safe vs Not Reef-Safe Triggerfish

There are some differences between reef-safe and not reef-safe triggerfish. Remember, there is always the possibility that a triggerfish that is labeled as reef-safe may not prove to be so in your own aquarium.

When talking about reef-safe and not reef-safe triggerfish, there are a few levels of compatibility. In general, most triggerfish will leave corals alone; if you find that a triggerfish has taken a bite of coral, it is more likely that there was an invertebrate on the coral than it is for the fish to intentionally go after the coral for food. However, there are some species that are more likely to intentionally or mistakingly eat corals than others.

Then, there are reef triggerfish that don’t eat corals or invertebrates. In the wild, these fish often rely on various types of zooplankton, like copepods, as their main source of nutrition. Not only is there a difference between food preferences with reef-safe versus not reef-safe triggers, but there are also behavioral differences.

Reef-safe species are anatomically different. They have smaller mouths that are higher up on the head to help them capture food in the water column. Because they depend on the water column for food, they are more likely to be in the open ocean than among the rocks.

Reef-safe species are also less likely to destroy your rockwork. Reef Triggers that rely on invertebrates and corals for food can be very determined. They will be spitting sand and will even pick up and move rocks in order to reach their food. In return, this can injure corals and make a mess in the aquarium.

In general, reef-safe species are also much less aggressive, though this varies from fish to fish. As always, not every reef-safe triggerfish will be completely safe for a reef aquarium, but there are certainly some species that do better than others.

Different Types

Though there are not many species of reef triggerfish, there are actually quite a few different genera:

• Melichthys
• Odonus
• Xanthichthys
• Rhinecanthus
• Bailstes
• Balistoides
• Pseudobalistes
• Sufflamen

From this list, Melichthys, Odonus, and Xanthichthys tend to be considered the most reef-safe, with Xanthichthys being the most confirmed success.

Each species from these genera will vary in needs, so it is always important to do plenty of research before you go out and buy a triggerfish! Especially since some of these species can be very, very expensive and grow to impressive sizes.

8 Best For Aquariums

Here are the top types of triggerfish that are likely to be reef-safe. Remember, this means that they are the species most likely to leave both corals and invertebrates alone. This can always change from fish to fish so don’t take the chance if you’re not willing to lose anything in your tank!

Due to spawning behavior in the wild, not many of these have been successfully bred in captivity. This can cause some prices to be higher and limit the availability of certain species.

1. Sargassum (Xanthichthys ringens)

• Species Type: Xanthichthys
• Scientific Name: Xanthichthys ringens
• Size: 10 inches
• Origin: Caribbean Ocean
• Tank Size: 125 gallons
• Available As Tank Bred: Not Available

The Sargassum triggerfish is also commonly known as the red tail triggerfish. These fish are named after the point in their juvenile stage where they hide among floating vessels of Sargassum algae until they are ready to survive open waters. Their second common name comes from their identifiable orangey-red tail at the end of their speckled bluish-grey body.

Sargassum triggerfish are very common to spot in groups among relatively shallow reef ecosystems throughout the Caribbean. There, they feed on crabs and sea urchins. In the reef, they won’t typically touch corals but might take a bite at any present invertebrates.

2. Bluethroat (Xanthichthys auromarginatus)

• Species Type: Xanthichthys
• Scientific Name: Xanthichthys auromarginatus
• Size: 9 inches
• Origin: Indo-Pacific Ocean
• Tank Size: 125 gallons
• Available As Tank Bred: Not Available

The bluethroat triggerfish, also known as the gilded triggerfish and bluechin triggerfish, is an expensive yet eye-catching aquarium fish. These reef triggerfish have a very obvious blue patch around their throat with a lighter dappled grey body and yellow margins on their fins.

The bluethroat triggerfish tends to be found on the perimeter of the reef in loose groups. They heavily rely on copepods as a source of food, which will translate into their aquarium diet.

3. Niger (Odonus niger)

• Species Type: Odonus
• Scientific Name: Odonus niger
• Size: 12 inches
• Origin: Indo-Pacific Ocean
• Tank Size: 180 gallons
• Available As Tank Bred: Not Available

The Niger triggerfish, also known as the red-toothed triggerfish, is probably the most commonly available type of reef triggerfish in the aquarium hobby. They have a silky blue body with hints of yellow on their throat; as their second name suggests, they may have maroon-colored teeth.

Though named after an African country, these fish have a large range throughout the warm waters of the Indo Pacific region. They live in very strong currents where they group together and feed on copepods and sea sponges.

Hobbyists have had some success keeping this aquarium fish in a reef tank. They tend to be safer to keep when small but can become quite aggressive to invertebrates and other fish as they age.

4. Crosshatch (Xanthichthys mento)

• Species Type: Xanthichthys
• Scientific Name: Xanthichthys mento
• Size: 11 inches
• Origin: Pacific Ocean
• Tank Size: 180 gallons
• Available As Tank Bred: Available

The crosshatch triggerfish shares the same secondary common name, red tail trigger, with the Sargassum triggerfish. In comparison, the crosshatch triggerfish is much more expensive and desirable due to its distinctive color pattern of black and yellow; the males have a red tail fin while the females have a yellow one.

These beautiful reef triggerfish can be found off the coasts of oceanic islands, including Japan, the Hawaiian islands, and Easter Island. There, they hunt copepods in schools.

This aquarium fish is one of the friendliest species of triggers and will leave most corals and invertebrates alone.

5. Pinktail (Melichthys vidua)

• Species Type: Melichthys
• Scientific Name: Melichthys vidua
• Size: 14 inches
• Origin: Indo-Pacific Ocean
• Tank Size: 180 gallons
• Available As Tank Bred: Not Available

The pinktail triggerfish has a very obvious broom like tail that is pastel pink, though the rest of their greenish-yellow body make them less desirable but more affordable. Unlike the other reef triggerfish on this list, these fish actually prefer marine algae and various detritus as their main diet. However, they will also eat smaller fish and invertebrates if given the opportunity.

That being said, many hobbyists have kept these fish in a full reef aquarium without too many problems. Of course, there is a chance that they will eat any present invertebrates but chances can be improved with more regular feedings.

6. Indian (Melichthys niger)

• Species Type: Melichthys
• Scientific Name: Melichthys niger
• Size: 14 inches
• Origin: Widespread
• Tank Size: 125 gallons
• Available As Tank Bred: Not Available

The Indian triggerfish, also known as the black triggerfish, is another common type of trigger. These fish have a near black body and matching fins, though the bases of the fins are outlined in light blue; in good lighting, these reef triggerfish have dark blue patterning all along their body, but this is difficult to see.

The exact native range of the Indian triggerfish is unknown. They are believed to be widespread, with increased concentrations around oceanic islands, like Hawaii. These fish mainly feed on various algae and zooplankton. They have an interesting relationship with spinner dolphins where they both congregate together while the fish feed on the dolphin’s feces and vomit.

These fish aren’t usually kept in reef tank setups, though they seem to be very similar to pinktail triggers in behavior and demeanor.

7. Picasso (Rhinecanthus aculeatus)

• Species Type: Rhinecanthus
• Scientific Name: Rhinecanthus aculeatus
• Size: 10 inches
• Origin: Indo-Pacific Ocean
• Tank Size: 180 gallons
• Available As Tank Bred: Not Available

Picasso triggerfish, also known as Humuhumu triggerfish (the official state fish of Hawaii), are very popular and often become the star of the tank. These fish are light tans and whites with paint splashes of yellow, blue, black, and brown.

Unfortunately, Picasso triggerfish can be very aggressive towards fish and invertebrates. Though they likely won’t touch any corals in the tank, they will gladly eat larger crabs, sea urchins, and shrimp. Some hobbyists have had luck with keeping them in full reef setups as juveniles, but their aggression often grows with them.

In their natural shallow reef ecosystems, Picasso triggers are territorial and enjoy the open water.

8. Clown (Balistoides conspicillum)

• Species Type: Balistoides
• Scientific Name: Balistoides conspicillum
• Size: 20 inches
• Origin: Indo-Pacific Ocean
• Tank Size: 300 gallons
• Available As Tank Bred: Available

The clown triggerfish is the fish that everybody wants. This is one of the most colorful and interesting fish to look at in the aquarium hobby, period.

Many beginner hobbyists would love to get their hands on one of these black and white polka-dotted fish. However, they can grow to extreme sizes and need extreme setups. For most, it’s simply unrealistic to keep a clown triggerfish in the typical saltwater reef tank. Unfortunately, this doesn’t stop many from trying to do so.

In the wild, clown triggerfish live on their own and are very rare to come across. They feed on a variety of different benthic invertebrates, making them safe for corals but a predator for crabs, shrimp, and other cleanup crew members. This is one of the few triggerfish species that are available as tank bred.

Species To Avoid

While reef triggerfish are beautiful, there are a few species that common hobbyists want to avoid. This includes:

Undulate (Balistapus undulatus).

Also known as the orangelined triggerfish, this fish is super aggressive. They will definitely eat invertebrates and likely go after other fish in the aquarium as well. Because of this, they should only be kept with bigger reef fishes or ones that are able to defend themselves through poison, venom, or other body armor. They have tough teeth and can damage rocks, acrylic, and fingers. Buyer beware.

Queen (Balistes vetula).

These triggerfish need to be treated like nothing less than royalty. Queen triggerfish can grow to an impressive two feet and can become incredibly aggressive to fish and reef invertebrates alike. This makes them almost impossible to keep in the home aquarium, but something to admire on public display or appreciated from diver videos (like the one above by Rumble Viral).

Where To Buy

Triggerfish are typically available at local fish stores and several online fish stores. However, you will usually find large or common reef triggerfish when looking to purchase locally. If you are looking for smaller, tank raised, or even the more exotic types like crosshatches, consider purchasing from an online fish store.

These fish tend to do well when shipped and imported, however, do not purchase from an online retailer unless there is a guarantee on the fish or the fish is a what you see is what you get (WYSIWYG) fish.

For retailers, I would consider salwaterfish for budgets, liveaquaria’s driver’s den for middle price, and TSM corals for the most exotic varieties. Triggers can be expensive. If you are going to spend, make sure your retail backs their fish with guarantees or a quarantine process.

Final Thoughts

Triggerfish catch the attention of many hobbyists due to their impressive sizes, bright colors, and fearsome sharp teeth. Though most reef triggerfish species are incredibly hardy, not many hobbyists can actually keep them in their home aquariums due to their potential size and behavior.

Triggerfish are predatory fish. While there are some species that are considered reef-safe, there is always the chance that they take a liking to your reef invertebrates or corals.

Got any experience in keeping triggers? Leave a comment below.

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📘 Want to learn more? This article is part of our complete Saltwater Fish & Reef Guide — your ultimate resource for marine fish, coral care, reef setup, and more.

After 25 years in the saltwater hobby, I’ve seen just about every disease that can hit a reef or fish-only tank — ich, velvet, flukes, and more. I’ve personally gone through the heartbreak of losing fish to diseases I didn’t recognize quickly enough, which is why I now run a strict quarantine tank for every new addition. Knowing what to look for and how to treat it fast can mean the difference between saving your fish and a tank crash. This guide covers the most common saltwater fish diseases I’ve encountered and the treatments that actually work.

Most Common Saltwater Fish Diseases

These are some of the most common diseases that are seen in saltwater fish.

1. Ich (Marine White Spot Disease)

Ich’s version is saltwater tanks is Cryptocaryon irritans vs Ichthyophthirius multifiliis – it’s freshwater version. It is considered a moderately serious parasite that infects fish. Ich is one of those parasites that you can either choose to eliminate entirely or manage.

For those that decide to manage it, you focus on having a low stress environment for your fish and managing with equipment like UV sterilizers, Ozone, Diatom filters, or an Oxydator.

Fighting Marine Ich is all about know it’s life cycle. The picture below from Charles Raabe posted on Humblefish’s website is a good illustration of how the cycle works.

Symptoms

• Salt-like white spots on fish usually on the fins or body
• White spots are spread out and can be counted. Too many to count would indicate a far more serious disease (Velvet)
• Flashing, scratching, twitching, and heavy breathing

Treatment

• Fallow period (fishless) is 76 days
• Copper like Copper Power
• Chloroquine Phosphate in quarantine system
• Hyposalinity in fish only or quarantine systems
• Manage with equipment like UV Sterilizers

2. Marine Velvet

Marine velvet is the most common of what I call the deadly 3. The deadly 3 are 3 of the most serious diseases in the saltwater hobby that have the potential of wiping out all the fish inhabitants of your tank. It is a disease that is not to be taken light, sometimes killing fish before symptoms show.

This disease requires a 76 day fallow period to eliminate and cannot be managed like Ich. You have to wipe it out completely. This disease is the #1 reason to quarantine your saltwater fish.

Symptoms

• Number white spots – so many that you can’t count. Almost dust like
• Flashing, scratching, twitching, and heavy breathing
• Fish sensitive to light
• Fish swimming to current to breathe
• Mysterious sudden deaths of inhabitants

Treatment

• Copper like Copper Power
• Chloroquine Phosphate
• Fallow period – 76 days
• Disease must be treated in a quarantine tank to fully eliminate

3. Brooklynella (Clownfish Disease)

Brooklynella is the 2nd most common of the deadly 3 saltwater fish diseases. It typically affects clownfish, which is how it got its name clownfish disease from. Other fish can be inflected, but their physical symptoms will look different as you will see white blotches versus white film.

This disease has the potential to wipe out all the fish in a saltwater aquarium. Like with velvet, you can only eliminate it by doing a quarantine and doing a fishless period (fallow) for 6 weeks.

The medication used here are powerful. Formalin is the old school way of bathing and is no longer available in several states. Chloroquine Phosphate is the drug of choice here, but also difficult to obtain.

Symptoms

• Powderly white film
• Almost web-like white film on fish in advanced stages
• Large white blotches on non-clownfish
• Sudden deaths with any physical symptoms

Treatment

• Formalin bath (if legal in your state) – Ruby Reef Rally can be used as an option.
• Formalin bath – 45 minutes
• If Ruby Reef Tally – 90 minutes
• Freshwater dips can be used if above meds are not available. Bathe for 5 minutes
• After bath – treat with Metro + Chloroquine Phosphate
• Seachem Metro for 14 days in aquarium and feed to fish with focus binding if fish is eating
• Chloroquine Phosphate
• Fallow period – 6 weeks

4. Uroema marinum

Uroema is the scariest and hardest to battle of the deadly 3. This parasite has a direct life cycle, which means it has no encrusted stage like Brook. While this may mean the parasite is easier to eliminate, that is not the case. This disease can live without a host, mainly feeding on detritus to maintain itself when fish aren’t available.

You simply cannot get rid of this disease once it’s in your aquarium. It is that much of a nightmare. You can manage after you get rid of fish with sympthoms by maintaining a very clean saltwater aquarium and not purchasing chromis fish – the pathogens favorite host.

This is the only disease of the deadly three where euthanasia is recommended. Once the red sores appears, it’s usually too late to help the fish. Medication used here are strong just like Brook and velvet. Do not take this disease lightly

Symptoms

• Red sores on fish
• Sores appear in a vertical line usually around the center of the fish
• Sudden death without physical symptoms

Treatment

• If no sores are present – Formalin or Rally bath to start
• If sores are present – Use freshwater dip. Also okay to use if medications are not available
• Cholorquine Phophate
• Seachem metro treated food with focus to treat internal infections
• Euthanasia with clove oil

5. Flukes

Flukes are a hidden parasite that you will often come across with large fish like Tangs. While not serious on their own, it is common for these flukes to cause secondary infections (usually bacterial infections) on the infected sites.

This is one of the few diseases on the list that you can treat for in a display tank using Prazipro or General Cure. You can also use a freshwater dip to provide relief to the fish, as long in this video by Meredith Presley.

Symptoms

• Lethargic fish
• Flashing, scratching, twitching, and heavy breathing

Treatment

• 5 minutes freshwater dip for immediate relief
• Prazipro or API general cure to treat 5-7 days, perform water change, then another 5-7 days
• Hyposalinity for 7 days

6. Black Ich

Black ich is parasitic flat worm that usually affects Tangs (picture source). Like flukes it is a moderately severe disease that can develop secondary infections. It has the same treatment as flukes and can be treated in the display tank

Symptoms

• Small black spots on body
• Spots are raised

Treatment

• 5 minutes freshwater dip for immediate relief
• Prazipro or API general cure to treat 5-7 days, perform water change, then another 5-7 days
• Hyposalinity for 7 days

7. Bacterial Infections

Bacterial infections are very serious in the saltwater hobby. There are two types – gram-positive and gram-negative. Gram-negative are more serious and unfortunately the most common with saltwater fish. These infections are typically secondary infections from aliments like Ich or flukes. Wounds will also cause infections.

Treating a bacterial infection requires antibiotics and a quarantine tank. Because there are so many different types of bacterial infections, multiple medications are used. Board spectrum medications are the best to use to get a handle on the infection.

Because you cannot differentiate between a gram-positive or gram-negative infection without a scrape and microscope, it’s best to assume all bacterial infections you come across are gram-negative.

If untreated, a bacterial infection will typically kill a fish. Most gram-negative infections will kill a fish within 1-2 days.

Symptoms

• Redness, soreness on body
• White film or fungus looking growths
• Cloudy eyes
• Fin & tail rot

Treatment

• 90 minute dip in Ruby Reef Rally (one of the active ingredients is an antiseptic)
• Antibiotic options
  • API Triple Sulfa
  • Seachem Sulfaplex + Neoplex
  • Spectrogram (only available via American Aquarium)
• Treat antibiotics for 7-10 days

8. Head & Lateral Line Erosion (HLLE)

HLLE is a condition that is typically associated with tangs (picture source). There isn’t a definitive answer as to why this condition occurs, but there are several theroies:

• Poor nutrition
• Stray voltage
• Carbon
• Stress

Since there this isn’t a disease but more of a condition, this can be treated without medication. Tackle this by addressing all possible causes. Feed your fish quality frozen food and greens like Nori for tangs. Use a ground probing to remove any stray voltage and get any carbon in your filter/sump out of your system.

HLLE will sometimes heal over time, other times the fish will have some scarring from the condition. It’s all dependent on how quickly you can address the issue.

Symptoms

• Discoloration of fish
• Looks like color is peeling off from fish
• White or grey fading of color in patches

Treatment

• Increase nutrition with quality frozen food and vitamins like Selcon
• Remove any stray voltage with a grounding probe
• Remove any carbon from your filter or sump
• If fish was treated with copper – increase nutrition condition may heal over time

9. Internal Infections & Parasites

Internal infections can either be worms, parasites, or bacterial infections. Since it’s difficult to tell what your fish has, it’s best to tackle this ailment with a broad medication. General cure + focus is the big practice here with Metro + Prazipro being another combo (General Cure has both).

This is a very common issue with imported fish, but also easy to cure if you catch it early. This is a condition that can be treated in a display tank, though best handled in a quarantine tank before the fish is introduced to the display system.

Symptoms

• Sunken bullies (like video)
• White stringy feces
• Skinny fish that can never gain weight

Treatment

• General cure + Focus mixed with food
• Treat for 10-14 days or until feces is no longer white for several days

10. Swim Bladder Disease

Swim bladder disease is an all too common issue with imported deep water fish. Wrasses in particular are the most common fish affected by this aliment due to poor handling by the importer.

I’ve personally dealt with this issue several times in my reefing journey. I got so frustrated with this from imported fish, I stopped buying wrasses online unless it was a what you see is what you (WYSIWYG) get wrasse.

You can do the 3 treatments below in the bullet points. Some cases get to the point where you will need to lance the fish to remove the gas bubble. This is an advanced techique that should not be attempted by a beginner.

If you are going to attempt the lancing method (see video above), try to get an experienced reefing member from a reef club or considering calling your local vet. Some vets have performed the procedure with large ornamental fish or koi.

Fish will usually die without treatment as they cannot compete for food and will be subject to bullying. I haven’t seen any swim bladder wheelchairs made for saltwater fish versus goldfish (where these devices are more common).

Symptoms

• Fish is unable to swim upright
• Fish unable to swim downwards
• Gas bubble present in belly

Treatment

• Epsom salt – one tablespoon per 5 gallons
• 30 minute Methylene Blue bath
• Metro + Neomycin + Focus in food
• Lancing (See video) do not attempt unless with an experienced reef or have a license vet perform it

11. Lymphocystis

Symptoms

Lymphocystis makes this list as it is confused by ich. The disease fortunately is rarely fatal. However, the bad new is this is a viral infection. The fish will continue to carry the virus for the rest of its life. It can be managed.

The healthier the fish is, the more likely this virus will stay in remission. Focus on putting your fish in a low stress environment with a great diet. The virus will come and go, but the your fish can live a healthy life carrying it.

• White color growth on fins and back of fish
• Starts small, then grows in size

Treatment

• There is no known cure
• Can put virus in remission by providing a low stress environment and high quality diet

How to prevent many health issues in your fish

Prevention is the best medication when it comes to disease. There are many things that you can do at home to help prevent many of these issues in your fish. Your favorite pet’s health depends on water quality, diet and levels of stress; however there is still more we could do for them! Here’s how:

1. Quarantine New Fish

This is your #1 preventative measure against diseases. Many saltwater fish are imported, which means they go through a lot of stress to get to your home. This stress lowers the fish’s immune system and makes them venerable to disease. Some importing practices are also not ideal, leading to several issues after getting the fish.

You can save yourself a lot of headache and tank crashes by quarantining. If you want to learn more about it, I have a great article on quarantining.

Not interested in quarantining fish? If so, consider working with an online retailer who specializes in quarantined or pre conditioned fish. My top two choices for these would be Live Aquaria’s Drivers Den or TSM Corals. Go with TSM Corals if you can fish the fish you want there – they have the best practices in the industry.

2. Provide A Quality Diet

To keep your fish healthy, it is important that they have a proper diet. A well balanced and species appropriate food will not only make them full but also less likely to fight with other individuals in the tank over meals! Top quality frozen food is the best food you can purchase for saltwater fish. You can also do cultivated live food like black worms, but I’m assuming many readers here don’t want to go that route.

For frozen food, there are two brands I highly recommend. LRS and Rod’s Food are the two best frozen food makers on the market. Both are difficult to find online, but you can find them at specialty fish stores.

3. Provide Pristine Water (Avoid Poor Water Quality)

Part of establishing a low stress environment for fish is providing quality water. For saltwater tanks, an aquarium sump is the best filter you can purchase. Use a sump to your advantage by installing quality equipment like protein skimmers too keep your tank filtered and consider getting an auto top-off unit to keep your salinity stable.

Saltwater tanks are different than freshwater tanks in that some may not need a traditional water changing schedule. Test your water quality with quality test kits and only change water to maintain your parameters. If you have a reef tank, consider investing in a dosing pump to keep your calcium, alkalinity, and magnesium levels up

4. Reduce Stress

There are a few ways to reduce stress. I explained water as one. The other would be shelther and tankmates.

For shelter, you can provide your fish with lots of rocks. A large amount of live rock and/or dry rock provides plenty of spaces for fish to get shelter in. For most reef tank setups, shelter will usually not be an issue.

Tank mates are the next. You want compatible tank mates. Too many territorial disputes and bullying from aggressive fish will lead to stress, injuries, and disease. Add your most passive fish first and your most aggressive last.

5. Purchase Captive Bred Fish

Captive bred fish are generally healthier and have a better time adjusting to a home aquarium environment. You can avoid a few of the aliments on this list like Swim bladder disease from purchasing tank bred fish. You will still come across Marine Velvet and other serious diseases, but you will lower your risk in getting outbreaks with healthier fish who are used to living in a captive environment.

Creating A Medicine Cabinet

Anyone who has multiple saltwater fish and tanks eventually deals with sick fish. Whether you quarantine or not, it’s a good idea to keep medication on hand for emergencies! Here are some common medications that can help – I’ve added them together in one table so they’re easy to read. Most are available online or at your local fish store. Purchase them now before you are in a bind. Many medications on this list have long shelf lives.

Type	Medications
Parasitic (External)	Copper Power, Prazipro, Ruby Reef Rally, Chloroquine Phosphate
Parasitic (Internal)	General Cure, Seachem Metroplex, SeaChem Focus (To Bind)
Fungal	API Fungal Cure
Bacterial	API Triple Sulfa, Seachem Sulfaplex, Seachem Neoplex

FAQS

Further Resources

It would be unfair for me to talk about saltwater fish diseases without mentioning Dr. Fish himself, Humblefish. His forum is the go to if you are dealing with sick or infected fish in the saltwater tank hobby. Give his forum a visit if you need immediate assistance. The community there is amazing. They can be a lifesaver in a hobby where Vets are hard to find with experience in these aquatic animals.

Final Thoughts

Saltwater fish diseases tend to be more serious then with freshwater fish. Because of this, quarantining is the best practice. If you come across a sick fish, take action right away. Use this guide to help identify what you are going against. If you have any questions, leave them in the comments below. Thanks for reading!

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📘 Want to learn more? This article is part of our complete Saltwater Fish & Reef Guide — your ultimate resource for marine fish, coral care, reef setup, and more.

Looking for a full Mandarin Goby care guide? I have you covered today on this beautiful, but tricky to care for fish.

The Mandarin Goby is a small fish with big personality. They are very hardy, but need a constant food supply to thrive. This guide will give you everything you need to know in order to keep your new fish healthy and happy! Let’s dive in!

Species Overview

Scientific Name	Synchiropus splendidus
Common Names	Mandarin goby, mandarinfish, mandarin dragonet, and green mandarin
Family	Dragonet
Origin	Western Pacific Ocean
Diet	Omnivore
Colors	Blues, greens, oranges, reds
Care Level	Difficult
Temperament	Peaceful
Minimum Tank Size	30 gallons
Max Size	3 inches
Temperature Range	76 – 82 degrees F
pH Range	8.0 – 8.4
Salinity	1.025 or 35 PPT
Reef Safe	Yes
Available As Tank Breed?	Rare

Origins And Habitat

It is crazy to think that such beautiful fish exist on their own in the wild. The mandarin goby is a spectacle to find around Pacific reefs. More specifically, they can be found in the Western Pacific Ocean, from the Ryukyu Islands below Japan to the barrier reefs off the coasts of Australia.

There, they live in and around shallow reefs and lagoons less than 60 feet in depth. They prefer silty bottoms littered with pieces of coral that won’t injure their underbodies. These islands of reef provide good hunting grounds for their favorite food, copepods, as well as other small invertebrates and microorganisms.

Interestingly, mandarin gobies are usually seen in small groups, foraging together among this rubble.

What Do They Look Like?

Mandarin gobies are some of the most beautiful fish in the fishkeeping hobby. Unfortunately, this, in addition to their relatively inexpensive price, causes them to end up in the wrong hands of inexperienced hobbyists. This beauty comes with extreme difficulty, which we’ll discuss later.

Mandarin gobies have a deep aquamarine body with swirls and spots of greens and oranges that lead into a spectacular large reddish-orange tail fin; they also have a very distinguishable red eye against a lighter green head.

These gobies have large pectoral fins that they use to navigate and hover over coral reefs and the seafloor. They also have impressive dorsal fins that can easily collapse or be raised for a sail-like effect. As we’ll discuss, these dorsal fins are also used for telling the difference between males and females.

Mandarin gobies are only 3 inches long at mature size, but they immediately catch the eye with their unparalleled colors. In fact, they’re one of the few species of fish to express true blue pigmentation.

Male vs Female

If planning to attempt to breed mandarin gobies in your own reef aquarium, then it is important to be able to distinguish a male from a female. Luckily, these fish are pretty easy to tell apart from each other, making it easy to obtain one of each.

The main difference between a male and female mandarin goby is the presence of an elongated spine at the front of the first dorsal fin. Males will have a noticeable point on top of their heads that cascades into a normal dorsal fin. Females will not have this spike and will have a rounded first dorsal fin instead.

Tank Requirements

In terms of setup, mandarin gobies are easy to keep. They do well in reef settings with lots of cracks and crevices for them to hide in and to forage for food. A soft substrate, like aragonite sand, will also keep their underbellies safe from jagged, coarser granules.

Mandarin gobies are actually considered a nano species and hobbyists have kept them in aquarium sizes as small as 10 gallons. However, these are expert hobbyists and the casual fish keeper will not be able to do this for dietary reasons we will discuss later.

Instead, these gobies should be kept in a minimum take size of 30 gallon tanks. An even larger tank will help maintain a steady food supply. That being said, even big tanks with mandarin gobies in them will still need to be fed supplements from time to time.

Should You Quarantine Them?

For being such a difficult fish to keep alive in the aquarium, mandarin gobies are actually quite resilient and have good immunity to most common aquarium diseases.

These fish are known to excrete a protective mucus that prevents them from getting the most common aquarium diseases, especially those that attack the external body like some parasites. In addition to this natural defense, most hobbyists don’t quarantine them due to their immediate dependency on a living ecosystem.

Placing a mandarin goby in quarantine is basically redundant. Most medications that could preemptively be dosed would end up killing any and all pods while unnecessarily stressing out your fish. This could potentially leave to a starving fish that might have been relatively healthy in the first place.

Instead of quarantining your mandarin goby, buy from a reputable local fish store. Introduce it to the main display and observe closely for any signs of sickness. The most important thing, though, is to get your goby regularly eating and accepting a variety of foods as soon as possible.

Mandarin Goby Care Guide

While mandarin gobies are mostly peaceful, they can be aggressive towards other fish around the reef, especially other similar-looking sand dwellers.

The same is true for keeping mandarin gobies with other mandarin gobies. However, given some time, multiple species of gobies are able to work out territories among themselves after a bit of fin nipping. If you have a male and female mandarin goby, then you might even have a breeding pair when all is said and done.

If planning on keeping more than one species of goby in the reef aquarium, it is imperative to have a steady source of copepods. This can be achieved through harvesting your own copepods as well as having a larger tank in general. You can also purchase pods from companies like Algaebarn.

Otherwise, mandarin gobies can be seen weaving in and out of the rockwork looking for food. They are shy fish and spend most of their time at the bottom of the tank, but they might venture up to the higher portions of the rockwork if hunting is good.

In general, if you see your fish picking at the rock, then there is food available. You should be concerned if your fish starts to become more lethargic or duller in appearance and is drifting from rock to rock without nipping at anything.

As we’ll discuss later though, some preferred tank conditions might make a mandarin goby addition more favorable than others.

Are They Poisonous?

You might’ve heard that the most colorful animals in the world are toxic, like poison dart frogs. Being one of the most colorful fish on the reef, does this mean that you need to worry about your mandarin goby killing the rest of the fish in your tank, too?

Yes, mandarin gobies do carry toxins. However, it’s something you’ll rarely ever have to worry about.

When threatened, these peaceful fish excrete toxic mucus that apparently has a disgusting odor as well. It isn’t exactly known how detrimental this poison can be to nearby life, but the smell of the mucus can be very noxious.

It is very rare for your fish to excrete this mucus as they are incredibly docile. However, if they are mishandled or threatened by another fish, they will use this as protection. The excretion of the mucus can be seen as fine filaments in the water radiating away from their bodies.

Having to excrete this mucus often stresses out the fish a great deal and it is likely that the fish will die shortly after. If this happens while in the reef aquarium, it’s advised to do a water change immediately and continue to monitor parameters. Once things are under control, look for the cause of the annoyance.

Tankmates

Mandarin gobies are reef-safe fish. They can be kept with an assortment of peaceful fish that won’t chase them around or try to steal their favorite places among the rockwork.

This can be troublesome with keeping mandarins with other gobies and blennies that might get too close to their territories. Though multiple goby species can be kept in larger tanks, it’s usually only recommended for much larger systems with a steady food supply and intricate rockwork.

Otherwise, mandarin gobies can be kept with clownfish, tangs, wrasses, and other common reef fish species as well as most invertebrates. However, these fish will not do well in aquariums with higher flow, like small polyp stony (SPS) coral systems that need lots of water flow. Excessive flow can make hunting difficult and might make them stay hidden within the rockwork.

As these fish typically stay towards the bottom of the tank though, they usually don’t irritate too many corals by floating over them.

What Do They Eat?

This is where mandarin gobies get difficult. Up to this point, mandarin goby care has been straightforward, though they’re unlike any other reef fish you might have kept before.

When looking at a mandarin goby, you realize just how small their mouth really is. These picky eaters have incredibly small mouths fit for eating one main invertebrate: copepods.

What are copepods?

When hobbyists refer to saltwater rock as being ‘live’, they mean it in a few ways. One of the most obvious ways is understanding that it houses microscopic beneficial bacteria that keep aquarium systems stable. Even more obvious than that though, are the many macroscopic invertebrates and organisms that also make rock come alive.

In this group of living macroscopic organisms are copepods. Copepods are a type of aquatic crustacean found in both freshwater and saltwater ecosystems. There are many different types of copepod all with different roles within the natural food web. But in the marine aquarium, they are regarded as members of the cleanup crew and are a key diet for some species.

Copepods are very small even though they are macroscopic. They can be very difficult to find in the aquarium, but they can sometimes be observed on the side of the glass, especially when a light is shone at night. The most recognizable feature about them is their two antennae that run perpendicular to their clear/white body.

In general, these animals are scavengers and help clean up microscopic waste. In return, they serve as food for some of our favorite challenging marine fish, like the mandarin goby.

Feeding Instructions

The most ideal way to feed your mandarin goby is by having a fully established and mature reef tank with a healthy population of copepods that will never expire and replenish itself. Even for the most advanced hobbyists, a self-sustainable copepod population within the main display is practically impossible.

Mandarin gobies are always searching for food and it’s rare that a copepod population will be able to replace itself at the rate at which it’s being eaten. The problem is that some mandarin gobies will only accept live copepods and reject all other foods.

In cases like this, the best way to keep your mandarin goby fed is by setting up another tank to grow and culture copepods. Don’t worry, this setup doesn’t need to be elaborate, but just enough to always have a steady population of copepods on hand to keep your goby fed.

Setting Up A Copepod Culture Tank

A copepod culture tank can be made with a 5-10 gallon spare aquarium or container (like the one example from Blue Reef Tank above). Most hobbyists have found fast-reproducing species, like Tigriopus and Tisbe sp., to be the most effective for keeping mandarin gobies happy; it is also possible to start with a mix of copepod species.

This spare aquarium should be seeded with copepods and raised to a water temperature of about 75° F for optimal reproduction rates. There should be some water movement throughout the aquarium from a small sponge filter. In order to keep salinity stable, freshwater top-offs may be necessary every couple of weeks.

Otherwise, there is no additional maintenance. In fact, you want to get the aquarium as dirty as possible so that the copepods have something to eat, like that algae that naturally grows on the sides of the aquarium.

Another alternative is setting up a refugium underneath the main display. Not only will a refugium increase nutrient transportation for your overall system, but they are a safe place for copepods to live and naturally refill the main display reef tank.

However, refugiums give less control over manually dosing copepods and having an idea of the overall population available within the system at any given time.

How Do You Know If This Fish Is Starving?

The most common cause of death among mandarin gobies is starvation. These fish can quickly devour large populations of copepods overnight; if you see your fish searching for food but not picking at the rock, then there might not be anything there to pick at and it might be time to replenish.

This is a very common mistake among beginner hobbyists as their reef tank is not mature enough and copepod populations run out within a few days of adding the fish. The only way to know how much your goby is eating is by constantly observing the behavior of your fish and seeing how many copepods are present at any given time; this can be done by shining a light into the aquarium at night and seeing how many copepods are present for a rough estimate.

In addition to having a healthy population of copepods, you can also supplement feedings with live brine shrimp and mysis shrimp. Some mandarin gobies will take frozen food alternatives to both of these, but they will usually prefer live foods most; this diet can get to be incredibly expensive and difficult to maintain.

Some lucky hobbyists have had mandarin gobies that would take regular flakes and pellets, but this is very rare.

Lastly, make sure that your fish is always vibrant in color and has a plump abdomen. A starving mandarin will have dull colors, a skinny body, and an overall lethargic demeanor.

Final Thoughts

Mandarin gobies are one of the hardest fish that can be kept in the aquarium setting. They don’t actually require much in the way of tank size, water parameters, or territorial needs, but their nearly-exclusive diet of live copepods makes them a huge challenge for keeping fed.

These are one of the most colorful gobies available, but their beautiful colors will take time and determination. These fish are not for every system even if you might think you have everything they need to thrive.

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📘 Want to learn more? This article is part of our complete Saltwater Fish & Reef Guide — your ultimate resource for marine fish, coral care, reef setup, and more.