Not furry, but we like them anyway.

Lawnmower Blenny

Salarias fasciatus

Also called Jewelled blenny, Banded blenny, Blennius fasciatus (original name)

SpeciesShort profile

From Indo-Pacific: Red Sea and East Africa to Samoa, north to the Ryukyu Islands and south to the Great Barrier Reef and New Caledonia1 2

At a glance the quick version

Length10 to 14 cm1 2 3

Sizesmall

Grazes algae from rocks all day

Full of personality and expression

Good at changing colour to blend in

3 2

Looks how to spot one

Elongated blenny

A long-bodied blenny in olive to brown, marked with dark bars and many pale spots of different sizes. Dark lines run along the front of the body and small blue spots dot the rear, giving a mottled camouflage look.2 1 3

Coloursolivebrowndark barswhite spotsblue spots2 1

Personality what they are like

Peaceful with most fish, though it may defend its patch against other blennies, gobies or dartfish in a small tank.3

Daily activity how busy a day looks

Moves from rock to rock grazing and perching; it is a good jumper.3 1

Grooming and care the hands-on bits

Best added to a mature tank with plenty of live rock to graze. Keep a secure lid on the aquarium.3

Home where they are happiest

Minimum about 30 US gallons (114 L) with plenty of live rock. In the wild it lives on very shallow reef flats, lagoons and weedy rocky areas from the surface down to about 8 m.3 1 2

Food basics what goes in the bowl

Grazes surfaces in the wild, and studies find detritus makes up much of what it eats. In the aquarium, offer marine algae, seaweed, spirulina and algae-based foods 2 to 3 times a day.1 2 3

Company who they like around

Adults are usually solitary; keep one per tank.1

The story where it all began

Marcus Elieser Bloch described it in 1786 as Blennius fasciatus. Georges Cuvier later made it the type species of his new genus Salarias. It is now one of the best-known algae grazers in the marine hobby.2

Fun facts for the dinner table

1
It can breathe air for short periods, which helps it live in shallow tide pools.1
2
Despite its nickname, plant matter is only a small part of its natural diet.2
3
It changes colour to blend in with its surroundings.2
4
It is sometimes called a rock skipper because of how well it jumps.3

Recognised by the official bits

IUCN Red List: Least Concern (assessed 2009)1

The care rhythm Furry Diary remembers it for you

A typical home-care rhythm for a Lawnmower Blenny. It is our own starting plan, not a vet's advice, and you can change every line in the app.

FeedingSmall amounts once or twice a dayevery day
Temperature checkevery day
Salinity checkevery week
Top-upTop up evaporation with fresh RO water, not salt waterevery day
Water testevery week
Water changeAbout 10 to 20% of the waterevery 2 weeks
Glass cleanevery week

Start a free diary

Bicolor Blenny

Tailspot Blenny

Midas Blenny

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Where this comes from

Every breed page shows where each fact comes from. If we got something wrong, sorry, we are pet people, not a science magazine. Tell us at [email protected] and we will fix it.

FishBase: Salarias fasciatus fishbase.seused for distribution, size, depth, habitat, diet, air breathing, IUCN
Wikipedia: Salarias fasciatus en.wikipedia.orgused for appearance, diet detail, colour change, history
Saltwaterfish.com: Lawnmower Blenny saltwaterfish.comused for care, tank size, diet, temperament

Checked 2026-09-30. Text is written in our own words from these sources.