Blueline Snapper

The Blueline Snapper (Lutjanus kasmira), also commonly known as the Bluestripe Snapper, is a brilliantly colored marine fish distinguished by its vivid yellow body, pale underside, and four striking electric-blue horizontal stripes. Its streamlined profile, bright yellow fins, and bold schooling behavior create an impressive display in spacious saltwater aquariums.

Native to a broad Indo-Pacific range extending from the Red Sea and East Africa across the Indian and Pacific Oceans to southern Japan and Australia, this species inhabits coral reefs, lagoons, outer reef slopes, caves, and wrecks. Adults frequently gather in large schools around reef structures, while juveniles may utilize seagrass beds near patch reefs. The species can reach approximately 16 inches in total length, making substantial swimming room essential for long-term care.

The Blueline Snapper is especially attractive in large fish-only aquariums and carefully planned predator or reef displays. Although it does not normally target corals, its natural diet includes fish and crustaceans, so smaller tankmates and ornamental invertebrates may be considered prey.

Quick Care Guide

Care Level: Moderate
Minimum Tank Size: 180 gallons
Temperament: Semi-aggressive
Diet: Omnivore
Reef Safe: With Caution
Region: Indo-Pacific, including the Red Sea, East Africa, Southeast Asia, Japan, Australia, and central Pacific islands
Scientific Name: Lutjanus kasmira

Tank Requirements

Provide a large aquarium with extensive open swimming space combined with substantial rockwork, caves, ledges, and overhangs. Blueline Snappers are active swimmers and naturally associate with reef structures during the day, so the aquarium should offer both unobstructed swimming lanes and secure areas for retreat.

A long aquarium footprint is particularly important as the fish approaches its adult size. Rockwork should be securely positioned while leaving enough open space for comfortable turning and cruising.

Strong biological filtration, efficient protein skimming, good oxygenation, and moderate to strong water movement are recommended. Snappers are active feeders and can produce a considerable nutrient load, particularly when maintained in groups. A secure aquarium lid is also advisable.

Diet and Feeding

The Blueline Snapper is an opportunistic omnivore with a strong carnivorous component. In nature, it feeds on fish, shrimp, crabs, stomatopods, cephalopods, planktonic crustaceans, and some algae.

In captivity, offer a varied diet of mysis shrimp, enriched brine shrimp, krill, chopped shrimp, clam, mussel, squid, and appropriately sized pieces of marine fish. High-quality marine pellets and frozen carnivore or omnivore blends can also be incorporated into the feeding routine.

Juveniles generally benefit from one to two smaller feedings daily. Larger established specimens can receive appropriately portioned meals once daily or several times per week depending on size and condition. Avoid relying on freshwater feeder fish.

Temperament and Tankmates

Blueline Snappers are social fish that frequently occur in schools in the wild. They can be maintained singly, but groups can create a particularly natural display when housed in an exceptionally large aquarium with adequate swimming space and filtration.

They are generally not highly territorial toward unrelated fish, but their predatory feeding behavior is an important consideration. Small fish that can fit into the snapper's mouth should be considered potential prey, even if they initially coexist without problems.

Appropriate tankmates include robust, similarly sized marine fish such as tangs, larger angelfish, triggerfish, large wrasses, rabbitfish, and other substantial community or predator species. Avoid very small gobies, firefish, small cardinalfish, and other bite-sized tankmates.

Reef Compatibility

Reef Safe: With Caution.

The Blueline Snapper is not primarily a coral feeder and can be maintained in large reef displays where its size and predatory behavior are appropriately considered. The primary reef compatibility concern is predation rather than direct coral damage.

Ornamental shrimp, small crabs, and other crustaceans may be eaten, and sufficiently small fish are also at risk. Larger snails and established corals are generally less likely to be targeted, although a large active snapper can disturb loosely secured aquascaping or delicate coral placements while swimming and feeding.

Water Parameters

Temperature: 75–80°F
Specific Gravity: 1.024–1.026
pH: 8.1–8.4
Alkalinity: 8–12 dKH

Maintain stable conditions with strong filtration and consistent maintenance. Stability in temperature, salinity, and pH is more important than attempting to maintain one exact value within these ranges.

Common Considerations

• Can reach approximately 16 inches and requires substantial open swimming space.

• Naturally forms schools, but keeping a group requires a significantly larger aquarium than housing a single specimen.

• May prey on small fish, ornamental shrimp, crabs, and other suitably sized invertebrates.

• Requires strong filtration because of its active feeding habits and eventual adult biomass.

• Best suited to large reef, fish-only, or predator aquariums with robust, appropriately sized tankmates.