Keeping the Fuzzy dwarf lionfish

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The Fuzzy dwarf lionfish is so called because its scale structure makes it appear indistinct to its prey. It's clever, cunning and cute, as Dave Wolfenden explains.

Small and manageable as a pet, Dendrochirus brachypterus has bags of personality for a lionfish — although it can still pack a punch and tank mates should be chosen with caution!

Found in virtually the entire tropical Indo-Pacific, it’s regularly available in the trade. It naturally inhabits shallow coastal areas, favouring weed-encrusted rocky outcrops and caves in which it can ambush small crustaceans.

It grows to around 15cm/6” in length and there are several geographic colour variants — ranging from a deep red morph, through to a rare silver and orange form with striking yellow pectoral and dorsal fins. Most on offer, however, exhibit a far more subdued coloration.

Nonetheless, these are still attractive fish, with their ‘fuzzy’ appearance  — created by a distinctive scale morphology — and striking patterns being used as cryptic camouflage when hunting.

Want one?

So what are the aquarium requirements of this diminutive lionfish and which species is it compatible with?

Potential owners should ideally replicate the rocky habitat which the species inhabits in the wild and, if caves and overhangs can be provided, the fish will often lurk underneath them in an upside-down position. Therefore be prepared for life with not the most active fish in the hobby…

One possibility is to make them the subject of a species aquarium; several living around an artificial bommie — or pillar of live rock — can be very effective and they rarely tend to exhibit aggressive tendencies towards conspecifics.

Lighting can be subdued. In fact, they will not display to full potential in typically intense reef-quality lighting, so if you have super-bright illumination in the aquarium at least provide some form of area sheltered from the brightest of the light — otherwise considerable stress may result.

Dwarf lionfish can be housed in smaller aquaria than larger cousins of the family Scorpionidae. That’s not just because of their size, but also because they are less active swimmers. However, they still need a fair amount of room and are by no means suitable for nano aquaria. Consider 150 l/33 gal as the minimum volume to comfortably house a single adult.

copyright © Richard Ling, Creative Commons

Why that name?

The Fuzzy dwarf lionfish’s scientific name Dendrochirus brachypterus comes from a quite a mash-up of Latin and Greek terms, and together means ‘tree hand.’

Dendrochirus refers to its branched pectoral fin rays, and ‘short wing,’ with brachypterus describing the relatively stubby appearance of the pectoral fins in general.

Are they reef safe?

D. brachypterus could be considered for the reef aquarium, and it’s not unknown for specimens to be seen in invertebrate aquariums.

Of course, this will limit tank mates to species which won’t fit into the lionfish’s ample mouth! Bear in mind that even these dwarf lionfish can consume surprisingly large prey, so damsels, blennies, gobies and other fish can be vulnerable — as can many shrimps and other mobile invertebrates.

By the same token, take care to ensure that the lionfish itself isn’t targeted by larger, more boisterous tank mates. Morays, triggers, puffers and other large specimens may harass it, so choosing compatible species is critical.

Feeding

Feeding D. brachypterus, as with other lionfish, can initially be tricky, at least if only frozen feeds are available.

Have a plentiful supply of live so-called ‘river shrimp’ when acquiring a new specimen, as these are invariably readily accepted and help to ensure adequate nutrition during the settling-in period.

This is especially important for such dwarf species, as research shows they are much more susceptible to starvation than larger-bodied family members, such as the ‘volitans’ lionfish (Pterois volitans). However, they will still go several weeks without food with seemingly little effect.

Weaning the lionfish onto frozen meaty foods can be a battle of wills and the owner must have great patience.

Some individuals will present few problems, but others can be stubborn. Get tongs or long-handle tweezers and try waggling strips of lancefish or other silvery fish in front of the Fuzzy. They’re very responsive to movement when it comes to prey detection.

Once a lionfish has accepted an item of frozen food, experience shows there should be no turning back and subsequent feedings will become straightforward. Eventually the fish will probably become swimming dustbins and it’ll be a challenge to prevent overfeeding!

One feed every other day is more than enough and show restraint as lionfish can easily eat far too much in one sitting!

It’s also best to avoid excessively large food items as these can be difficult to digest. Due to their healthy appetites, even small species are capable of generating considerable pollution.

Filtration should be capable of coping with the ammonia spikes and other changes in short and long-term water quality associated with the intermittent feeding of such predators, especially if a few specimens are housed together.

Healthy signs

While they are generally extremely hardy, common sense should prevail when selecting a specimen. Behaviour in the dealer’s holding tanks should demonstrate a bright and alert fish, and if it’s possible to see one feeding all the better.

Quarantining new specimens is highly recommended and introduction and settling in should take place in subdued lighting.

The usual range of marine diseases can affect dwarf lionfish, but they respond well to most treatments and, provided water quality is maintained at optimal levels, they should be extremely tough additions to any aquarium.

Dwarf lionfish will occasionally shed their skin in the same manner as the related Leaf scorpion fish (Taenianotus triacanthus).

At first it’s a little disconcerting to witness, but is probably done to slough off accumulated ectoparasites and may warrant close investigation of the fish’s health status as well as the aquarium’s water quality.

Think of this occurence as a possible early warning...

Sting treatment

The 13 dorsal fin rays are each linked to a venom gland and D. brachypterus is capable of delivering an excruciating sting — despite its miniaturised appearance. Although it isn’t generally outright aggressive in the aquarium accidents do happen, primarily through careless handling or inattentive maintenance.

Should a sting be experienced, the accepted treatment is immersion of any wound in water of 45°C/113°F  — certainly not boiling — to destroy the protein-based venom. Even so, this treatment may not be entirely effective and the resulting wound may become infected and need greater medical attention. Getting stung by any lionfish is decidedly un-user friendly!

Will they breed?

There are few reliable reports of this species spawning in captivity, although full closure of the life cycle is yet to happen. They are known to be dioecious —the sexes being separate — with the male and female taking part in a relatively simple spawning ritual.

Some sources claim that males can be distinguished by a slightly larger head, longer pectoral fins and larger number of bands on those fins. Spawning appears to be internal and the eggs have a frothy, gelatinous mucus coating which helps keep them afloat for the first few hours after spawning.

Netting them without traumas

Take care when netting any lionfish — although they really shouldn’t be handled at all — that the spines don’t get entangle in the net. This can traumatise them, as well as creating a hazardous situation for the aquarist who has to cut it out! Very fine-meshed nets are best, as the fish’s spines tend not to become stuck in the material.

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