Undulate Triggerfish

Orange-lined Triggerfish

Family: Balistidae Picture of an Undulate Triggerfish or Orange-lined Triggerfish, Balistapus undulatusBalistapus undulatus
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We just bought a undulate trigger fish without looking at it’s deadly lifestyle and it went into a 4 foot tank with a balloon puffer fish, dog face puffer fish... (more)  Amelia Graham

   Even though he's a beauty, this guy has the reputation of being the most aggressive triggerfish! Which means the Undulate Triggerfish or Orange-lined Triggerfish may be the most aggressive fish, period! Actually they are okay when they are small, but get cantankerous as they get older.

   Make sure you have a large aquarium or not very many other fish. Give it lots of room and a cave or rocks to retreat into.

   The Undulate Triggerfish or Orange-lined Triggerfish can be worth keeping since it is lively, colorful, and will grow to be a nice pet, taking food from the owners' hand! Watch your fingers though, the teeth are very sharp and can deliver a painful bite.

For more Information on keeping this fish see:
Guide to a Happy, Healthy Marine Aquarium

  • Kingdom: Animalia
  • Phylum: Chordata
  • Class: Actinopterygii
  • Order: Tetraodontiformes
  • Family: Balistidae
  • Genus: Balistapus
  • Species: undulatus
Undulate Triggerfish adult, Balistapus undulatus

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Very beautiful, very mean

The Undulated Triggerfish is as beautifully striped as it is mean. As juveniles, they are not as aggressive but they become 12" murderous monsters as adults! If you want to keep them alone in a 180 gallon tank as the only fish, then by all means buy one! Just be careful when you put your hand in the tank, as these nasty buggers can leave quite a nasty bite mark on your hand, arm, or whatever else it can grab. Still not wary? Then this is the fish for you! They make grunting sounds, spit water, chew electrical cords, are generally obnoxious and will steal your credit cards! Undulate Triggerfish have been known to chomp through clams, which is good because they need to wear down those ever growing teeth.

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Maintenance difficulty:    The Undulate Triggerfish or Orange-lined Triggerfish is easy to keep. Triggers are among the hardiest of all marine fish.

Maintenance:    Feed all kinds of live, frozen, and flake foods. Best to feed small amounts several times a day. We generally feed squid, shrimp (the same kind people eat), mussels, and all kinds of chopped up fish.

Habitat: Natural geographic location:    Undulate Triggerfish or Orange-lined Triggerfish are found in the Indo-Pacific: Red Sea south to Natal, South Africa (Ref. 4420) and east to the Line, Marquesan and Tuamoto islands, north to southern Japan, south to the southern Great Barrier Reef and New Caledonia. Occurs in coral-rich areas of deep lagoon and seaward reefs from the lower surge zone to at least 50 meters.

Foods:    Feeds on a variety of benthic organisms such as algae, echinoderms, fishes, mollusks, tunicates, sponges, and hydrozoans. All kinds of meaty foods including starfish and sea urchins, snails, mussels, calcareous algae, and pieces of passing fish.

Social Behaviors:    Generally this fish is aggressive towards other fish, especially other triggerfish. Has a territorial nature.

Sex: Sexual differences:    Unknown. Eggs laid as one cluster in a shallow excavation on sand or rubble along channels.

Light: Recommended light levels:    No special requirements.

Temperature:    No special requirements. Normal temperatures for marine fish is between 74 and 79 degrees Fahrenheit.

Length/Diameter of fish:    Undulate Triggerfish or Orange-lined Triggerfish adults can grow to 30 cm (12 inches).

Minimum Tank Length/Size:    A minimum 60 gallon aquarium is recommended.

Water Movement: Weak, Moderate, Strong    No special requirements.

Water Region: Top, Middle, Bottom    No special requirements.

Availability:    This fish is available from time to time.

Lastest Animal Stories on Undulate Triggerfish

Amelia Graham - 2019-05-26
We just bought a undulate trigger fish without looking at it’s deadly lifestyle and it went into a 4 foot tank with a balloon puffer fish, dog face puffer fish and 2 foot snowflake eal and we thought the 4” trigger would be fine with two 6” puffers but we were so very wrong it bit the dogface puffer with intent to kill and took over the balloon puffer’s home and as soon as he went for a nibble on the balloon puffer my amazing eal hit him away after that we put the “nice” trigger in quarantine.We are returning him in the morning.:(

AR - 2009-03-13
I have an Undulate Trigger living with a Yellow Tang... they have been together since they were babies and believe it or not they are best buds... every now and then the tang will cross the line and the Undulate gets a little nasty but the next day all is well. What I find most odd is the Undulates behavior of building... this guy will literally move all of the sand, gravel, rocks and coral in the tank to one side... he builds these huge mountains on one side of the tank and leaves only the glass on the other side... each time I go in to clean the tank I level off the sand and gravel and move the rocks back, he goes crazy and starts attacking me... than within a few days the mountain is rebuilt... I have had saltwater aquariums for years and have never encountered this behavior.. it's amazing to watch him work tirelessly and I am actually starting to feel bad about re-arranging his home...:-)

  • Anonymous - 2011-05-17
    He is building a place to sleep. You need to provide a cave for him.
steve - 2011-01-26
I had an undulated with a yellow tang, a lion fish and a very fast damsel. When the trigger got mad he would actually change colors, kind of an electric blue striped brown color. And I swear when he got really mad he would grunt or bark at the other fish. I called him cave boy because he only came out to kill something. I eventually returned him for a huma, much better tank mate.

LC - 2010-12-20
I got a 5-6"ondulatus trigger! He ate a 6" panther grouper,5" niger,4'5" picasso! He's a beautiful KILLER! They were in a 75 gallon tank! Got along all together for about 2 years till one day he decided to be alone! Within a week he ate the other fish! He's been alone for about six months now! I'm working on getting a nice size lion fish! Can't wait.