Six Line Sweetlips - Plectorhinchus diagrammus

Six Line Sweetlips (Plectorhinchus diagrammus)

The Six Line Sweetlips is a striking marine fish known for its elongated body, bold horizontal striping and characteristic thick lips. Juveniles can differ noticeably in appearance from adults, while mature fish develop a more substantial body shape and stronger patterning. Peaceful towards suitably sized tankmates but capable of reaching a large adult size, this species is best suited to spacious marine aquariums with excellent filtration and carefully selected companions.

Common Name:
Six Line Sweetlips, Sixline Sweetlips

Scientific Name (Latin):
Plectorhinchus diagrammus

Maximum Size:
Approximately 60 cm

Water Type:
Marine

Origin / Natural Habitat:
The Six Line Sweetlips occurs in tropical Indo-Pacific reef environments and is associated with coral reefs, lagoons, reef slopes and sheltered areas containing substantial rock and coral structure.

Juveniles often remain close to cover, while adults may range across broader reef areas in search of food.

Water Parameters:
Temperature: 24–26°C
pH Range: 8.1–8.4
Salinity: SG 1.024–1.026
Nitrate: Low and stable
Ammonia/Nitrite: 0 ppm

Temperament:
Peaceful to Semi-Aggressive

The Six Line Sweetlips is generally peaceful towards fish that are too large to be viewed as prey.

As it grows, very small fish and ornamental invertebrates may be at risk, so tankmates should be selected with its adult size and feeding behaviour in mind.

Diet:
Carnivore

The Six Line Sweetlips naturally feeds on a variety of benthic invertebrates and other small marine prey.

In the aquarium, offer a varied diet including chopped prawn, mussel, cockle, squid, krill, mysis and other suitably sized meaty marine foods.

Newly introduced specimens can sometimes be reluctant to accept prepared foods, so careful feeding observation is important.

Minimum Tank Size:
Approximately 1,000 litres

Its very large adult size and active swimming behaviour mean the Six Line Sweetlips requires a substantial aquarium with generous horizontal swimming space.

Behaviour & Activity:
The Six Line Sweetlips is an active but generally calm marine fish that spends much of its time cruising around reef structure and open water.

Provide substantial swimming space together with secure caves, overhangs and large areas of stable rockwork.

Juveniles may behave more secretively than adults and can spend considerable time close to shelter.

Reef Safe:
With Caution

The Six Line Sweetlips does not typically target healthy coral tissue, but it should be considered reef safe with caution.

Shrimp, crabs, worms and other smaller invertebrates may be eaten as the fish grows.

Its eventual size also makes it unsuitable for many conventional reef aquariums.

Special Requirements or Care Notes:
This species should only be purchased with its substantial adult size and long-term space requirements fully considered.

Provide a very large, mature marine aquarium with excellent filtration, strong oxygenation and plenty of open swimming room.

Tankmates should be robust and large enough not to be viewed as prey.

Avoid highly aggressive species that may intimidate juveniles or prevent them from feeding.

New specimens should be monitored closely to ensure they begin feeding consistently.

Secure rockwork is important, as large adults can easily disturb loosely positioned décor.

Suitable for:
Experienced

Availability:
Availability can vary depending on season, collection area and supplier.

All images are a visual representation of the fish you will receive, made to be as accurate as possible. Please note that Mother Nature is a wonderful thing, and variation in patterns and colours will occur — that is part of the unique beauty of these animals.