Blennies

Blennies are the best value in a marine tank. They stay small, they cost little, several of them do useful work on algae, and they have more personality per centimetre than anything else we sell. Gallery Aquatica stocks five species at our shop in Tingalpa, east of the Brisbane CBD.

Blennies are in-store purchase and pickup only. We do not send live fish by courier or freight. Ring 0420 484 584 to check what is in.

What blennies are like to keep

Most blennies perch rather than swim. They wedge themselves into a hole in the rock with just the head out, watch the tank, and dart out to graze or investigate. That makes them excellent value in a smaller tank, because they use the rockwork rather than needing open water.

They are peaceful toward other fish but territorial toward each other. One blenny per tank is the rule unless the tank is large and the species differ - two blennies competing for the same hole will fight.

They also need caves. A blenny with nowhere to wedge itself is a stressed blenny, and it will spend its time hiding behind equipment instead of on display.

A note on fang blennies

The canary blenny below is a fang blenny (Meiacanthus), which carries a pair of grooved venomous teeth in the lower jaw. These are defensive - the fish is not aggressive and poses no realistic risk in normal keeping or handling.

It is actually an advantage. Predatory fish learn quickly to leave fang blennies alone, so they are safer in a mixed tank than their size suggests. Worth knowing about rather than worrying about.

The blennies we stock

The photographs below show each species for identification. They are not photographs of the individual fish currently in our tanks — stock changes week to week, so ring 0420 484 584 to check what is in.

Lawnmower Blenny (Salarias fasciatus, jewelled rockskipper)

The algae grazer, and the reason most people buy a blenny. Mottled brown and cream with a blunt frog-like head and raised eyes. Reaches 13 cm and wants 300 litres.

It grazes film algae off glass and rock continuously, and a healthy one will keep the panels noticeably cleaner. But there is an important caveat: it eats film and short turf algae, not hair algae, and it needs an established tank with enough of it to live on. A lawnmower blenny added to a clean new tank will slowly starve, and they do not readily switch to prepared food. Add one to a tank that has an algae problem, not to prevent one.

Reef safe. Occasionally rests on coral, which can irritate it, but does not eat it.

Midas Blenny (Ecsenius midas)

The unusual one. Where other blennies perch, the midas swims in open water like an anthias - golden-yellow with a slim eel-like body and blue-ringed eyes. It will often join a shoal of anthias or chromis and behave as though it is one of them.

Reaches 13 cm and wants 200 litres. Feeds on plankton rather than algae, so it takes prepared food readily and does not depend on an established tank. One of the easiest and most rewarding blennies. Reef safe.

Bicolour Blenny (Ecsenius bicolor)

Front half slate brown, back half orange, with a blunt head and a permanent expression of mild suspicion. Reaches 10 cm and works in 110 litres, which makes it one of the few marine fish genuinely suited to a small tank.

Hardy and characterful. Takes prepared food readily and grazes a little algae alongside it. Territorial toward other blennies. Reef safe, though it will occasionally nip at coral polyps - less often than a dwarf angel, but it happens.

Canary Blenny (Meiacanthus ovalauensis, yellow fang blenny)

Plain, bright, uniform yellow with a slim body and a forked tail. Reaches 10 cm in 110 litres.

A fang blenny, so it swims confidently in open water rather than hiding - predators leave it alone. Peaceful, hardy, takes prepared food immediately, and one of the best small marine fish for a beginner. Reef safe.

Other blennies we regularly stock

Also part of our regular range. Ask us in store or ring 0420 484 584 for size and temperament.

• Tiger Blenny

Which blenny should you buy?

For a first blenny, or a small tank: the canary or the bicolour. Both are hardy, cheap, undemanding and work in 110 litres.

For something more interesting to watch: the midas, which behaves like no other blenny and shoals with your anthias.

For algae control: the lawnmower - but only in an established tank that already has film algae for it to eat. It is not a preventative measure and it will starve in a clean tank.

Tankmates

Blennies suit almost everything peaceful: clownfish, gobies, chromis, anthias, Banggai cardinals, tangs and dwarf angelfish.

Keep one blenny per tank. If you want two, choose species with different habits - a midas swimming in open water and a lawnmower grazing the rock will generally ignore each other, whereas two perching Ecsenius will not.

Avoid lionfish, morays and larger triggerfish, all of which will eat a blenny. The canary blenny's venomous fangs give it more protection than the others, but it is not worth relying on.

Common questions

Do you ship blennies?

No. All marine fish are in-store purchase and pickup only. We do not send live fish by courier or freight.

Are these blennies in stock right now?

These are the species we stock as our regular range, not a live inventory. Ring 0420 484 584 or email shop@galleryaquatica.com.au to check.

Do lawnmower blennies really eat algae?

Yes, film and short turf algae off glass and rock, and they graze all day. They do not eat hair algae. Importantly they need an established tank with algae already present - one added to a clean new tank will starve, because they rarely switch to prepared food.

What size tank does a blenny need?

A bicolour or canary blenny is comfortable in around 110 litres. A midas wants 200 and a lawnmower 300, mostly because of the grazing area it needs rather than swimming space.

Can I keep two blennies together?

Only with care. Blennies are territorial toward each other and will fight over the same hole. Two species with different habits - one open-water swimmer and one rock grazer - have a much better chance than two similar perching species.

Are blennies reef safe?

Broadly yes. The midas and canary take no interest in coral at all. The bicolour occasionally nips polyps, and the lawnmower sometimes rests on coral and irritates it without eating it.

Is the canary blenny venomous?

It is a fang blenny, with a pair of grooved venomous teeth used purely in defence. It is not aggressive and presents no realistic risk in normal keeping. The main effect is that predatory fish learn to leave it alone.

Which is the easiest blenny for a beginner?

The canary blenny. It takes prepared food immediately, is peaceful, stays small, tolerates a range of conditions, and does not depend on an established algae supply the way a lawnmower blenny does.

More marine fish

See all the marine fish we stock, or the Brisbane store page for coral and equipment.