Lions and triggers and eels
my! Nothing embodies both the beauty and danger of the oceans
more than lionfish. Not only are they astonishingly beautiful
with their gracefully flowing fins, dramatic colorations,
cautious movements, and fish-gulping mouths, but they're equipped
with venomous spines capable of delivering painful stings
upon an unwary hobbyist. In spite of all this bravado, lionfish
are peaceful, extremely hardy and disease-resistant tank inhabitants
that are well suited for the intermediate saltwater hobbyist.
Two beautiful lionfish in flight. This photo displays
the pectoral fins of both the P. radiata (left)
and P. antennata (right). Both fish are
approximately 8 months old and 7-8" long. Photo
by Frank Marini.
A Lionfish for Any Tank?
The very popular Volitans
lionfish is considered the ultimate lionfish by most marine
aquarists, and other members of this genus, such as the Antennata
and Radiata, lionfish are frequently found at local
fish stores. As adult fish, they are considered medium sized
(10-15" long with tail) and, while they are relatively
inactive swimmers, they still must be housed in a fairly large
aquarium (75 gallons or more). So, does this mean that people
with smaller tanks can't enjoy lionfish? Certainly not. Another
type of lionfish, the "dwarf lions," fills this
niche and is commonly available. Dwarf fuzzy lions, dwarf
lions, and Fu Man Chu lions stay reasonably small (under 8"
long including tail) and do very well in tanks in the 30-50
gallon range. These smaller lions are every bit as beautiful
as their larger cousins, may also pack a powerful sting, and
ingest proportionally sized foods (Burgess, 1991). Let me
start out by mentioning that common names for lionfish vary
from place to place, and one person's "turkeyfish"
is someone else's Russell's lion. I see this incorrect identification
of lionfish weekly at local fish stores; almost every tank
of lionfish for sale contains misidentified species, and they
are all lumped into two groups: large lionfish are all called
Volitans lions, and any small lionfish are identified
as "dwarf lionfish" (Michaels, 1999). While I frequently
use common names to describe certain species of lionfish,
it is preferable that we identify these fish by species names.
In this way, both interested parties understand which fish
are being discussed [Figure 1].
1. An imposing view, face-to-face with a 12"
long P. volitans lionfish. This lionfish will
reach a maximum size of 15" within eighteen months.
A fish this size requires an appropiately sized large
tank. Photo by Frank Marini.
Classification and Distribution
Lionfish are members of the
scorpionfish family (Scorpaenidae) and, in particular, the
subfamily Pteroinae. There are 5 genera and approximately
16 individual species in the taxon, with two of these genera
and 11 of the species common in the saltwater hobby (Eschmeyer,
1986). The two genera available to hobbyists are Pterois
and Dendrochirus; these fish are easily identified
by both the adult size of the fish and the shape of their
beautiful pectoral fins. In Dendriochirus lionfish,
the pectoral rays do not reach the base of the caudal peduncle,
and, in general, the fin rays are branched and form a solid
fan shape by a connecting membrane that spans each fin ray.
Pterois lionfish have elongated fins reaching well
past the tail, with many fin rays individually sheathed in
a long flowing membrane.
Lionfish are found in the
Indo-Pacific (central and western Pacific oceans) and the
Red Sea. A few of the lionfish have a wide distribution, such
as the Russell's lionfish (Pteriois russelli), which
are found on both reef and rocky environments in subtropical
and tropical waters, while other lions have extremely limited
ranges, such as the Hawaiian lionfish (Pterois sphex),
which are found only in waters surrounding the Hawaiian Islands.
Captive Care of Lionfish
The size of the aquarium needed
to house one or more lionfish will depend on the species of
lionfish chosen. Members of the smaller dwarf lionfish can
be kept in smaller tanks. Because these fish are sedentary
and tend to hide in the rockwork or upside down in caves,
smaller tanks (between 30-55 gallons) are suitable [Figure
2]. In general, members of the Pterois family (the
mid-to-large bodied lions) require larger tanks in the range
of 50-100+ gallons. Adult P. volitans can easily reach
15" in length and should not be kept in tanks smaller
than 75 gallons. I have read many posts from people who have
kept these fish in far smaller tanks, so my advice to them
is to be prepared to provide a larger tank within a year or
so, as this is the time required for these fish to reach adult
2. Lionfish like this Dendrochirus sp remain
under 7" and can be easily kept in a 55 gallon
tank. Photo by Frank Marini.
Requirements for aquascaping
can vary between species; almost all lionfish are dawn/dusk
predators and will spend much of their time during the day
lounging and hiding. The Antennata and Radiata
lions will hide almost exclusively during daylight hours,
so caves and covered rockwork are useful, while Volitans
lions prefer open waters day and night. Dwarf lions initially
will hide during the day; however, once acclimated they will
spend much of the day light hours in open view. Juvenile fish
of all lionfish species are quite timid and spend daylight
hours hiding in the rockwork. The good news is that most lionfish
will acclimate to tank life and your individual lighting schedule,
so after a few months of hiding and lounging, they will begin
to spend much of their time out in the open. According to
Michaels (1998), lionfish are ideal candidates for reef aquariums.
While I agree that these fish won't harm any corals, they
limit tankmate selections [Figure 3]. If a reef tank
has no fish equal to or smaller than the lionfish, no ornamental
shrimp or crabs, then lionfish are acceptable. I would say
that housing a lionfish in a reef is your decision, as I have
seen both beautiful reef tanks with dwarf lionfish as occupants,
as well as a reef tank with no other fish life than a Volitans
3. Lionfish in a reeftank? Sure, it can be done,
and the dwarf lionfish make a great addition, just be
aware that they will eat any small fish or moving invertebrate
that they can fit into their cavernous mouths. Photo
by Frank Marini.
The Line-up of Lions:
Common Lionfish Species
(listed by increasing size)
Common name: Fu Man Chu lionfish
Maximum size: 5-6 inches, minimum tank size:
Commentary: The Fu
Man Chu lionfish is a diminutive lionfish that can be readily
identified by two large whiskers that protrude from either
side of its mouth [Figure 4]. The fish is red-orange
with blackish specks. The two solid pectoral fins resemble
fans from a Spanish Dancer, and are circular with the lower
fin rays forming angular points. This fish is a poor swimmer;
instead, it tends to scurry across the substrate and will
occasionally hop. Out of all the lionfish I have kept, Fu
Man Chu's are one of the more aggressive lionfish towards
same species fish. I have not been able to introduce two Fu
Man Chu lions in my 180-gallon tank without one Fu harassing
the other to the point of sickness. What is remarkable with
Fu Man Chu lionfish is their prey stalking behavior. Once
a prey item has been identified, the fish will approach and
begin to shake its head and gill covers from side-to-side
[Figure 4a]. When in capture range of the food item,
the lionfish will begin to rhythmically twitch its dorsal
spines back-and-forth, and as it readies to gulp the prey
item, it vibrates the lower portions of its pectoral fins
The Fu Man Chu lionfish is
one of the more difficult lionfish to keep in the home aquarium
because they ship very poorly and they don't readily wean
from live to prepared foods. These fish are among the most
shy and cautious lionfish I have ever owned, and it is imperative
that caves and hiding spots are made available for this fish
to hide. Initially, they spend much of their time hiding in
the rockwork and will only come out to feed. These fish will
have problems competing with fast swimming fish for food,
and unless they are target fed, will starve. Live ghost shrimp
should be among the first foods offered to establish this
fish onto an aquarium diet, and once it is comfortable and
begins coming out from hiding, the aquarist can begin to wean
the fish onto prepared foods. I have had great success using
Piscine Energetics Mysis shrimp as an enticing prepared
food by simply thawing the frozen Mysis and squirting
it out of a tube in front of the hungry Fu Man Chu. Over the
years, I have kept three Fu Man Chu lionfish, and it took
over two months to wean the slowest one from live foods.
4. A side view of a Fu Man Chu lionfish. Notice
the two "whiskers" that distinguish this lionfish.
Also, notice their unique coloration; no other lionfish
possess this much orange. This picture is typical of
a Fu Man Chu lionfish, slithering on the rockwork. These
fish walk more often than they swim. Photo by Frank
4a. Shown here is the second dorsal fin and its
twin eyespots which identify the "biocellatus"
or two eyes. The Fu Man Chu will vibrate this fin in
the hope of distracting and confusing potential prey
and predators. Photo by Frank Marini.
5. A Fu Man Chu lionfish heading into the rockwork
to hide for the day. Photo by Frank Marini.
Common name: Dwarf fuzzy lionfish
Maximum size: 7-8 inches, minimum tank size:
Commentary: The Dwarf fuzzy lionfish is probably the
best of the dwarf lions that a hobbyist can keep in an aquarium,
mainly because they are hardy, disease resistant, readily
weaned onto prepared foods, and are actively swimming lionfish.
These fish have a unique fuzzy texture to their scales and
possess semi-circular pectoral fins that are decorated with
stripes and patterns. The fin rays are short and connected
with solid webbing. During the day, D. brachypterus
tend to hang upside down in caves or on soft corals. During
the dawn/dusk periods, dwarf fuzzy lionfish become very active
and swim about in search of food. After a few months in captivity,
all of my dwarf fuzzy lionfish have learned to swim towards
me whenever I walked into the room, and they continue to swim
and beg for food while I'm present [Figure 6].
6. A dwarf fuzzy lionfish. This little lionfish
has learned to beg for food, and when he sees me come
into the room, he immediately rushes to the top of the
tank and spits water out the top. Photo by Frank Marini.
Dwarf fuzzy lionfish come
in three-color varieties: drab brownish [Figure 7],
beautiful reddish [Figure 7a], and a rare yellow form
[Figure 8]. Of course, combinations of reds and yellows
and browns and reds exist as well. The most common in fish
stores are the brown/reds and the brown/drab yellowish. However,
I have seen a few solid red Dwarf fuzzies and I did find two
solid yellow Dwarf fuzzies in the past 10 years. Adult male
Dwarf fuzzy lions are readily identified by having a larger
head, longer pectoral fins (the fin tips reach past the caudal
peduncle), and have between 6 to 10 bands (or stripes) on
their pectoral fins. Female Dwarf fuzzy lionfish have only
4 to 6 stripes. In the wild, Dwarf fuzzy lions live singly
or in groups of three to 10 individuals, but in a large home
aquarium (100 gallons or greater) it is possible to keep a
large dominant male and several females. I have kept a trio
of Dwarf fuzzy lionfish for many years, and my male would
routinely breed with a female. In smaller tanks only one specimen
is recommended as Dwarf fuzzy lions will harass conspecifics
within a size-limited tank habitat. Out of all the lionfish
species, Dwarf fuzzy lionfish might be the best suited for
a reef tank; they have small mouths, don't usually bother
similarly-sized fish, and tend to stay to themselves.
Shown here is a Japanese lionfish Dendriochirus bellus.
This cold-water lionfish is very similar to the dwarf
fuzzy lionfish, and occasionally makes its way into
the U.S. aquarium trade. Photo courtesy of H. Uchiyama
7. The brownish drab coloration of a typical dwarf
fuzzy lionfish. Notice the blue eyes and band patterns
on the pectoral fins. Of importance is that its pectoral
fins stops well before the caudal peduncle and has fewer
than six defined bands. Photo by Frank Marini.
7a. A solid red dwarf fuzzy lionfish. While not
as common as a solid brown lionfish, these red lions
do occassionally appear at the local fish stores. Photo
by Frank Marini.
8. The rare yellow
form of a dwarf fuzzy lionfish. According to Michaels,
this color morph is located in one central location:
the straits of Lembah. This fish commanded a $350 USD
price tag. Photo by Frank Marini.
Common name: Dwarf lion or Dwarf zebra lion
Maximum size: 6-8 inches, minimum tank size:
Commentary: The Dwarf
lionfish are beautiful lionfish in a small package. These
little lions are among the most common lionfish found in the
hobby. Dwarf lions are characterized by a dark spot on the
lower portion of the gill cover operculum, and concentric
bands on the inner portion of the pectoral fins. The pectoral
fin membranes extend almost all the way to the fin ray tips,
and form a solid web. The body pattern consists of alternating
dark brown and light brown stripes. This species demonstrates
very subtle sexual differences, and in my experience is impossible
to sex by appearance. Husbandry of a Dwarf lion is exactly
the same as keeping a Dwarf fuzzy lionfish. The most important
points are providing the fish with plenty of good hiding spots,
providing a nutritious and varied diet, and maintaining good
water quality [Figure 9].
9. Face-on with a dwarf zebra lionfish. Notice the
broad striping patterns which identify this species.
Photo by Frank Marini.
Common name: Antennata lion, Spot-finned lion
Maximum size: 8-9 inches, minimum tank size:
Commentary: Antennata lions are a hardy, medium-sized
lionfish for the home aquarium. Antennata lions are
beautifully marked with alternating vertical bands of reds,
whites, and browns, and are readily identified by their pectoral
fins which possess webbing that connects only halfway up the
fin ray [Figure 10]. This membranous area has one or
more dark spots resembling eyespots. The posterior portion
of each fin ray is whitish and extends to past the caudal
peduncle on the ventral portion of the pectoral fin; each
fin ray is independent and not connected by webbing [Figure
10a]. There are no readily identifiable sexual markings
on these fish. In the home aquarium Antennata lionfish
are shy and will spend a lot of their initial time in the
tank hiding. If multiple Antennata lions are present,
the aquarist will need to ensure that each has its own hiding
spot. In my experience, these fish prefer shrimp over fish
for food, but are readily established on ghost shrimp first,
then weaned onto prepared foods using Piscine Energetics frozen
Mysis or whole krill.
10. An upside-down P. antennata lionfish.
Using the pectoral fins as a guide, one can identify
antennata lionfish. Notice the single row of
spotting nearest the pectoral base, and the membranous
connection, which terminates less than 1/2 the way up
the fin rays. Photo by Frank Marini.
10a. A P. antennata lionfish in motion. Again,
notice the single row of spotting on the pectoral fins,
a trait which helps identify this species. Photo by
Common name: Devil lionfish, Mombassa lion, deepwater
Maximum size: 7-8 inches, minimum tank size:
Commentary: These deep-water
lionfish are found mainly on South African reef slopes. They
are usually found inhabiting sponge and soft coral beds in
search of food, and feed almost entirely on crabs. Devil lions
are almost always misidentified at the fish store as Antennata
lions [Figure 11]. Four main characteristics distinguish
them. First, Devil lions have larger eyes and, in fact, the
eyes look out of proportion to the head. Second, the vertical
striping patterns on Mombassa lionfish are red or deep reddish
with a unique texture to the pattern, almost fuzzy looking.
Third, the lower portion of the pectoral fin on a Mombassa
lion has three or 4 fin rays that are webbed [Figure 11a].
This is not the case in Antennata lions. Fourth, the
pectoral fin of a Devil lion has multiple eyespots throughout
the fin, not just around the attachment, as in Antennata
lions. The care of Devil lionfish is similar to that of Antennata
lionfish. I have found Devil lions to be intolerant of harassment
by any fish, although they may swallow any fish smaller than
them and they are particularly intolerant of poor water quality.
These fish are often the first fish to succumb to bacterial
infections that effects their eyes (resulting in a cloudy-eyed
appearance) as water quality declines.
11. One, two, three, mombasse!
deep into the eyes of a devil lionfish. In this photo
you can readily distinguish a striping pattern different
than an antennata lion, a finely textured pattern.
Also, notice the large prominent eyes. Photo by Frank
11a. Peering out of some rockwork, this P. mombasse
looks around inquisitively for food. Again, the large
wide eyes are prominent in this photo. Also notice there
are multiple rows of spots at the base of the pectoral
fins. Photo by Frank Marini.
Common name: Radiated lion, Clearfin lion
Maximum size: 9-10 inches, minimum tank size:
lions are found primarily in the Red Sea, and in my experience,
they ship poorly to the wholesalers and pet stores, possibly
because of their remote location in the wild. So, finding
a good healthy Radiata lion can be difficult. These
lions are also considered rare in the wild, are therefore
not frequently seen in the lionfish trade, and they subsequently
command a higher price. In my opinion, they are among the
more beautiful lionfish, as the markings and patterns on them
are so variable that they are almost chameleon-like [Figure
12]. The body markings consist of alternating wide vertical
bands of dark red, browns, black-reds, red-greens, all separated
by a sharp white stripe. The caudal peduncle has two vertical
bands that point toward the tail fin [Figure 12a].
The second dorsal, anal and caudal fins are clear and without
spots or markings. The pectoral fins are spectacular white
rays with membranous webbing only on the bottom quarter. When
Radiata lionfish swim, they extend their pectoral fins,
accentuating the white stripe pattern. In the home aquarium,
Radiata lionfish are one of the more difficult lionfish
to keep for a number of reasons. First, they usually arrive
at the fish stores in poor condition. Second, they are passive
lionfish and do not compete well for food against any fast
swimming tankmates. Third, they are intolerant of poor water
quality and often succumb to illness as water quality declines.
Fourth, I have found these lions to prefer to eat shrimp and
crabs over fish, and I've had to establish them using ghost
shrimp and small fiddler crabs as first foods [Figure 12b].
Once they are established on these foods, however, it is difficult
to get them to accept prepared foods, but with patience, they
may accept other foods and will survive quite well in the
12. A P. radiata lionfish on display. This
photograph does wonders to demonstrate how the large
body stripes of a Radiata lionfish are interspersed
with white lines. Radiatas have 2 large single
ocular projections and no lower lip projections. Also,
notice the pectoral finnage on this species; the rays
are connected with a curved red membrane. Photo by Frank
12a. This photograph demonstrates the beautiful
color patterns of Radiata lionfish. Notice the
long sweeping pectoral fins and note the 2 vertical
stripes on the caudal peduncle. These two stripes are
found on all Radiata lionfish. Photo by Frank
12b. An adult Radiata lionfish, seen here
in an upside-down position. This 10" fish is both
large and in charge of the tank. Lionfish are underwater
acrobats and will swim in any, and all, directions to
acquire food. Photo by Frank Marini.
Common name: Russell's lion
Maximum size: 10-12 inches, minimum tank size:
Commentary: One of
the smaller members of the Volitan lionfish group,
Russell's lionfish are hardy, pollution tolerant lionfish
for a medium to large aquarium [Figure 13]. In the
wild, Russell's lionfish are found in coastal South African
waters near silty mud flats and estuaries, where they feed
primarily on small fish and crustaceans. Russell's lions are
one of the more commonly available lionfish in the hobby,
and are frequently misidentified as "red Volitans".
Juvenile Russell's lions have a whitish body with dark brown
vertical stripes [Figure 13a]. The pectoral fins are
pale white with light brown and blue spotting. As the animal
grows and ages, the body pattern becomes more diffuse and
turns rust-brownish in color, while the pectoral fins turn
darker and lose the spotting. The second dorsal, anal, and
caudal fins are clear with an occasional brown spot. The head
features two ocular projections and a few lower tassles that
hang off the mandible.
13. A Russell's lion. Once you know the color pattern
of Russell's lionfish, you will never make the misidentification
of a Volitans again. Russell's lionfish have
spot-free clear fins, and their body patterns are white
with large infrequent stripes. Photo by Frank Marini.
As aquarium residents, Russell's
lions adapt easily and quickly to aquarium life. They almost
always wean to prepared foods, only requiring a few days of
starvation to entice them to eat a "wiggling" silverside
or chunk of krill. Russell's lions spend almost all their
time out in the open and will often swim boldly with other
tankmates in search of food. I have found these fish to grow
fairly quickly when fed properly, and they will easily become
10 inches long within one year [Figure 13b].
13a. A juvenile Russell lionfish, similar to what
is commonly seen at local pet stores. This little 4
inch juvenile possesses long flowing pectoral fins and
will grow into a foot-long fish eater within one year.
Photo by Frank Marini.
13b. The same lionfish 1 year later. Sure, I feed
them well, but look how big they get. Russell's lions
are eating machines, and will easily outgrow a 55 gallon
aquarium within 8 months. If you noticed that the body
of this fish is getting thicker and the pectoral fins
are appearing shorter, you are correct. Older Russell's
lionfish have fat, squatty bodies and relatively short
pectoral fins. Photo by Frank Marini.
Common name: Volitans lion, "lionfish", turkey
Maximum size: 12-15 inches, minimum tank size:
Commentary: When someone
states they have a lionfish, this is usually the fish they
are describing [Figure 14]. The most common lionfish
in the hobby, the Volitans lionfish are hardy and pollution
tolerant lionfish that are great inhabitants for a large aquarium.
In the wild, Volitans lions spend dawn/dusk periods
in open water in search of foods (primarily fish), and frequently
travel in packs of multiple animals (5 or more). During the
daylight hours, they head to cave openings and protected structures
The coloration of Volitans
lions is both variable and attractive. These fish are generally
sold in two color morphs: a red form with reddish/brown stripes
[Figure 14c], and a black morph, with black markings
[Figure 16]. The amount of black or red varies with
the collection locale of these fish, and even solid black
Volitans have been seen at my local fish stores. Juvenile
Volitans lions have wonderful busy vertical stripes
alternating with lighter and white outlines [Figure 15].
The pectoral fins are disproportionately long; each ray is
individually webbed, and the center of the pectoral fin is
frequently clear. As these fish age, the striped body pattern
becomes more diffuse and the pectoral fins "appear"
to shorten, resulting in a squatty large-bodied fish with
14. A juvenile P. volitans lionfish. This
is the typical dark brown (red) color morph. The striping
pattern varies on almost all of these fish. What is
noteworthy is that the center of the pectoral fins is
almost translucent. Also, Volitans lionfish have
multiple mandibular projections, and two ruffled ocular
projections. Photo by Frank Marini.
14c. The same lionfish, pictured one year later.
Like the Russell's lionfish, P. volitan lionfish
grow like weeds. This 13" long fish is a Hoover
in lionfish stripes. The pectoral wingspan on this fish
reached over 18" wide, hammering home the point
that Volitans lionfish require big tanks. This
fish can easily consume any medium sized angel, wrasse,
or dwarf lionfish. Photo by Frank Marini.
In the home aquarium Volitans
lions make beautiful and interesting "centerpiece fish."
Frequently offered for sale as 2 inch juveniles, they are
cute and adorable with tremendous personality. Juveniles are
active swimmers and are constantly searching out food. Volitans
lions almost always wean over to prepared food quite well,
usually with no more assistance required than adding shrimp
or fish chunks to the water column. Volitans lions
are aggressive feeders and will actively compete with other
fast swimming fish like tangs and wrasses. These fish are
pollution tolerant and are the most hardy and forgiving of
the aquarist's negligence of all lionfish. The main problem
with Volitans lionfish is their size; the cute 2"
juvenile fish at the store will reach 8-10" in one year's
time (with proper feedings) and within 6 more months it will
obtain a maximum size of 15". These fish easily outgrow
their tankmates and will frequently eat them. Any fish that
is equal to half the body size of the Volitans lion,
is considered food, and will be eaten in time. Additionally,
a 15" long fish with a large pectoral fin span requires
a large aquarium, and even though these fish tend to be more
sedentary as adults, they still need to turn around, so an
18" wide tank is recommended at a minimum.
15. A P. volitans perched on the rockwork.
Unlike many of the dwarf lionfish, Volitans lionfish
will spend much of their time out in the open searching
for food. Photo by Frank Marini.
16. A headshot of a black "morph" of P.
volitans. This adult lionfish has lost its juvenile
ocular projections and has taken on a large bulldog-like
jaw line. Photo by Frank Marini.
The biggest challenge faced
by a lionfish owner is providing a proper nutritious diet.
Of all the problems I see with lionfish, improper nutrition
and its results are the predominant health issue for captive
lionfish. In the wild, lionfish eat smaller fish and invertebrates.
Unfortunately, in the home aquarium lionfish will readily
accept live wiggling feeder fish like feeder goldfish or rosy
red minnows. The reason this is a problem is that only freshwater
feeder fish are available to hobbyists and they do not provide
the proper nutrition. In fact, a lionfish fed exclusively
with goldfish will frequently die prematurely due to a number
of feeder fish-associated problems. A study by Toonen et
al (Toonen, 2000) demonstrated that freshwater feeder
fish of the carp family (like goldfish, rosy reds, etc.) are
very high in fats and lack all the marine based highly unsaturated
fatty acids (HUFAs) required for proper health of marine fish.
Of all the freshwater feeding choices available to the hobbyist,
ghost shrimp are the best of what's available. Ghost shrimp
can be enriched in marine-based HUFAs by being fed any marine
flake food or marine plant material, and I have not found
a lionfish yet that will ignore a ghost shrimp. The best way
to ensure a lionfish remains in proper health is to feed it
a varied diet of fresh and frozen seafoods. With that said,
I would recommend to anyone keeping a lionfish to establish
the fish in the aquarium by temporarily using freshwater feeders
such as ghost shrimp, guppies, mollies, rosy red minnows,
and goldfish for 2 weeks up to 1 month maximum. After this
establishment period, the lionfish must be weaned off these
feeders and onto marine-based prepared foods.
However, this is where another
problem begins. Most lionfish require their food to "look"
alive for them to eat it, and this wiggling motion by potential
prey items triggers their innate feeding response. One of
the better methods to wean lionfish onto prepared foods is
to starve the fish for 3 or 4 days, then introduce a small
intact lancefish or "silverside" (this is a saltwater
minnow packaged in 25, 50, or 100 packs and commonly available
at most local fish stores). I find it best to impale this
silverside onto a clear acrylic rod (the feeding stick) and
"wiggle" it away from, but in full view of the lionfish
[Figure 17]. The key point is that you have to convince
the lionfish that this dead food is actually alive. Some people
impale the silverside on a chopstick, or use their fingers
(I do not recommend this method) and wiggle it. Once weaned
onto prepared foods, I recommend rotating through many marine
based foods, such as chopped gulf shrimp (with their shell
on), lobster tail, crabmeat, strips/chunks of marine fish
(available at the grocery store), and chunks of squid and
octopus. I also recommend supplementing these foods by adding
a few drops of a vitamin (such as Zoe or VitaChem),
and marine HUFA boosters like Selcon or Zoecon.
It may take time to encourage
a lionfish to eat non-living foods, but this weaning process
is the most critical key to success in lionfish husbandry.
In my experience a "hungry lionfish is a brave lionfish,"
and the use of starvation prior to offering prepared foods
is often a key to success. If feeding live foods is desired,
grass shrimp (harvested from saltwater), fiddler crabs, small
shrimp or saltwater harvested minnows are good choices. Additionally,
it is usually easier to get a younger lionfish to switch over
to non-living foods than an older animal.
Just being lazy, hanging about on a rock. This is a
typical pose for a lionfish while they are resting,
digesting or waiting for food. Photo by Frank Marini.
After being weaned onto prepared
foods, these fish often learn to beg for food. Try to avoid
the temptation to overfeed. Lionfish are gluttonous and, if
fed continuously, will grow too quickly (possibly resulting
in health issues and a shortened life span) and generate undesirable
amounts of waste in the tank water.
It is important not to offer
a lionfish large prey items, or large chunks of food, as reports
have suggested that lionfish have been killed by food rotting
in their gastrointestinal (GI) tract. According to Michaels
(1998), lionfish will occasionally kill themselves due to
overeating. While I have not experienced this, I have found
that lionfish will eat to the point of regurgitation, and
even this sign of overeating should be avoided. Problems with
overeating can be avoided by offering multiple smaller food
items, rather than one large one. In fact, if a lionfish is
given the choice between a large fish and many small ones,
it will normally choose to eat the smaller fish first. In
the wild, a lionfish will consume from 1 to 11 small to medium-sized
prey items per feeding, then retire to a hiding spot to digest
the food for a day or so, and repeat this process. Therefore,
I would recommend feeding lionfish to the point of seeing
a small bulge in their abdomen two to three times weekly.
I also recommend starving lionfish for a few days to accurately
recreate their natural dietary intake and, in fact. a 3-feedings/week
schedule is sufficient to ensure proper growth.
17. The weaning basket. This basket is placed in
the tank and protects newly acquired scorpionfish from
the other fish, while I train them to eat prepared foods.
Utilizing the basket, I can keep a watchful eye on the
feeding of my new fish, as well as acclimate the fish
to my tank and its tankmates. I have found the weaning
basket to be a key in allowing a stubborn new fish the
time it requires when feeding in a hostile environment.
You can see in the basket that I have acquired another
Yellow Dwarf fuzzy lionfish. Unfortunately, this one
is another male. Photo by Frank Marini.
Those Beautiful Fins
Lionfish are hunters and ambush
predators, plain and simple. Because they hunt, they have
adapted their body shapes to facilitate their prowess. One
of the most remarkable features of lionfish are their pectoral
fins. These fins may vary in size, but are flamboyant, colorful,
and very mobile. When a lionfish stalks it's prey, it uses
the pectoral fins to perform a number of tasks, often swaying
its pectoral fins from side-to-side and slightly forward,
an action which seems to make its approach less distracting
to the intended victim [Figure 18]. Additionally, by
tilting the fins forward, it creates a barrier or fencing,
and herds the prey to a certain spot restricting its movement.
As the lionfish moves in closer, preparing to swallow the
food item, the pectoral fins are frequently tilted and shaken
(most likely to distract the prey and, just as importantly,
to allow the lionfish to focus on the eye of the food). Large
Volitans lions will often drag their pectoral fins
across the bottom of the aquarium, with the hope of flushing
out any hiding food items. Similarly, in the dwarf lionfish
species, the fin movements are frequently exaggerated when
hunting. Members of the dwarf fuzzy lionfish twitch their
dorsal and pectoral spines when hunting. Fu Man Chu lionfish
have a unique rhythmic sequential back-and-forth twitching
of their dorsal spines, and they vibrate only the ray tips
of their pectoral fins when hunting prey items. The dorsal
spine movements are thought to distract and confuse prey and
enhance the lionfish's hunting ability. Most lionfish are
brightly colored under the lighting of the home aquarium.
However, in low-light situations, like those found at dusk
and dawn, the brightly colored markings become dark disruptive
patterns that serve as a camouflage, making the lionfish less
visible to potential prey. The pectoral fins also serve another
purpose: when threatened by a predator, a lionfish will often
spread these fins widely, orient its head facing down to aim
its venomous spines forward, and presents a formidable and
menacing target to the attacker. In a few lionfish species,
the inner pectoral fins have boldly marked eyespots and, when
displayed, these eyespots may scare off or confuse potential
18. The backside of a dwarf fuzzy lionfish. What
you can see here is that the lionfish has flared its
fins in response to feeding. These lionfish use their
pectoral fins to herd and trap their prey. Photo by
One of the most common questions
I address is, "What else can I keep with my lionfish?"
The answer is a complicated issue [Figure 19]. Frequently,
hobbyists want to keep multiple lionfish in the same aquarium,
and although there is no problem housing two or more of these
fish together, closely related lionfish will fight. I have
found this problem occurring most frequently with the dwarf
lionfish, in that Dwarf Fuzzy lionfish will often harass Dwarf
Zebra lions. Although these skirmishes are often nothing more
than gill cover flaring, head shaking, and chasing, many times
it's accompanied by a bite or two. If one lionfish persistently
attacks another, they should be separated or the subordinate
lionfish will cease feeding and may die. Another point of
consideration when keeping both large and dwarf forms of lionfish
together is that large lionfish will eat smaller lionfish,
and I have personally witnessed this on several occasions.
19. Potential tankmates for lionfish. I find that
planktonic feeding triggers, large tangs and a few larger
fish (like the Jewel damsel) make suitable tankmates
for lionfish. Once you have a tank full of lionfish,
you'll wonder why the tank looks so empty. Nobody's
swimming. Inevitably, you'll want a few swimming fish.
Photo by Frank Marini.
Special considerations need
to be used when selecting tank mates for lionfish. Lionfish
will eat any small fish or crustacean that fits into their
cavernous mouths. Even though lionfish are venomous, lionfish
are not immune to being harassed or even eaten by other fish.
Large eels, frogfish and other scorpion fish are all predators
of lionfish in the wild. According to Michaels (1998), large
angelfish, pufferfish, and triggerfish are also known to harass
lionfish. Triggerfish are notorious for nipping off the dorsal
spines before killing lionfish. However, I have found the
planktonic feeding triggers (Blue cheek, Pink-tailed, Niger)
to behave more predictable towards lionfish, and I would consider
them compatible tankmates. Because of the small confines of
many aquariums, lionfish have been known to impale tankmates
with their venomous spines. Envenomation likely occurs for
several reasons: the lionfish may be retaliating for a prior
attack and intentionally impales the fish, or a tankmate accidentally
swims into the venomous spines. When jabbed by a lionfish
spine, the victim will usually develop a good size lesion
at the point of impalement and the area will become inflamed,
reddened, and necrotic. Other signs of the venom on impaled
fish are increased breathing rates, distress, color loss and
decreased swimming. In many instances, death will occur. According
to Michaels (1998), most fish injected with a large dose of
lionfish venom (more than what is injected with just one spine)
will die with 30 minutes.
Diseases and Health Problems
Lionfish are hardy fish, and
if fed well and provided with good water quality, almost never
contract diseases or parasites. It is important to note that
a thin membranous lining called a cuticle covers lionfish.
Since lionfish are sedentary fish, the cuticle is used to
protect the lionfish from settling organisms. In fact, lionfish
will occasionally shed their cuticle to remove any unwanted
hitchhikers. A shed cuticle looks like a large mass of whitish
stringy mucus, and this shedding occurs when a lionfish just
start flashing around the aquarium, trailing white stringy
mucus behind it. Cuticle shedding is also a sign of improper
health in lionfish, as stressed lionfish or lionfish kept
in poor water quality will increase shedding behavior. The
most common disease problems I have seen are fin rot (a bacterial
infection which is treated with antibiotics), cloudy eyes
(also a bacterial infection) [Figure 20] and dinoflagellates.
Lionfish do get ich, and this condition can be treated with
hyposalinity or copper based medications. As far as other
health issues, the major problems I have observed are starvation
and lockjaw. Both occur suddenly, and usually in an established
fish that has adapted well to captivity. In regards to the
issue of starvation, the lionfish just stops feeding, and
over a few weeks period cannot be enticed to eat by either
live or prepared foods. Starvation is usually a result of
long-term improper diet caused by the exclusive feeding of
one type of food (freeze-dried krill is generally the most
common cause because it's widely available and convenient).
This diet can potentially cause a blockage of the gastrointestinal
tract, or result in a nutritional deficiency, or result in
the formation of a goiter. Lockjaw occurs when the lionfish's
mouthparts stay fixed in the open position. I have observed
this on many occasions. It is unclear what causes this problem,
but I have observed lionfish unintentionally ingesting substrate
during feeding or banging their mouthparts into rockwork when
hunting food items and this may account for part of the problem.
Over the course of a few days, fish with this condition were
able to work their jaws closed again, but the alignment of
the jaw was never perfect in any case, and their jaws would
20a. A P. mombasse with severely cloudy eyes.
Sadly, the Mombasse lions are quite sensitive
to deteriorating water quality, and are the proverbial
"canary in a coal mine". These cloudy eyes
can be successfully treated with an antibiotic regimen.
Photo courtesy of buddamonk.
All members of the family
Scorpaenidae possess venom glands in their dorsal, anal, and
pelvic spines. The primary function of these spines is a defensive
measure against conspecific threats and predators. The amount
of venom injected from each spine is dependent on how much
pressure is being placed on the spine and the amount of time
the spine is left in the tissue. In the home aquarium, lionfish
stings are very rare, but do occur. In fact, there are three
main events in the normal course of owning a lionfish that
may increase the chances of being stung. The first occurs
when the lionfish is transferred from a shipping bag, or when
transferring the lionfish from one tank to another. The reason
your incidence for getting stung is high here is that you
are maneuvering around a lionfish that is close to your hand.
The lionfish will often be exposed and may thrash around in
defense, or might fall out of one container to the next, with
an inadvertent sting as a result. The second most common activity
that increases the likelihood of getting zapped by a lionfish
occurs while cleaning the tank. While the lionfish won't rush
towards you or race across the aquarium, the act of putting
your hands into the lionfish's environment serves to put it
on alert. They will often hide under the very rockwork being
rearranged or the glass being cleaned nearby. Being a quite
curious fish, they might also think you are introducing food,
and they may hover nearby. Lastly, through some unfortunate
event, you might trap or corner a lionfish in the tank, and
cause the lion to become defensive.
Shown here is another Japanese lionfish called Paraterois
heterura. This unique lionfish has caudal rays which
extend into long finnage. This fish is similar in size
to P. antennata. Photo courtesy of H. Uchiyama
Getting Stung... It Can Happen To You
In general, lionfish are fairly
peaceful fish that are not really interested in the mundane
tasks of an aquarist cleaning the tank or doing water changes.
However, there can be exceptions. One day I was cleaning my
tank, vacuuming the substrate, moving the rockwork around
and, apparently during this time, I was wiggling my fingers.
All my lionfish (and scorpionfish), are trained to take silversides
and meat strips when I wiggle the food in front of them, so
I assume a few of the fish were coming over to consider if
my fingers were food. I initially just shooed them away, but
one of them was persistent and kept coming back. At one point,
I was contemplating where to place the next rock and not really
paying attention to the task, but my hand and arm were submerged,
and I felt something brush my arm. Reflexively, I jerked my
hand back, and this sudden movement spooked the lion sufficiently
for him to immediately point head down with his dorsal spines
extended. I impaled myself onto his outstretched spine. I
immediately pulled my hand out, looked at where the spine
entered ("Whew, no blood!"), and continued cleaning
the tank. After about 30 seconds, I realized what was happening.
A pain started throbbing around my hand, up to my wrist, and
then stopped. At first, it was like a bee sting in intensity,
and the pain increased for another 5 minutes. At that point,
it felt like a bee sting on steroids! This happened back in
1990, when there was little, if any, knowledge on what to
do for a lionfish envenomation. I rushed to the emergency
room (concerned mainly by what I had read online about lionfish
stings and their venom). I was very scared, and what made
matters worse was that the doctor had never heard of a lionfish,
or a scorpionfish! Since the physician had little idea what
to do, he treated the wound like a wasp sting. He rubbed the
area with a strong corticosteroid solution, and put me on
a strong antihistamine. The pain lasted for about 20-30 minutes;
my hand throbbed and ached, even burned at times. My hand
suffered from numb areas for about 3 days after this event.
Stupidly, I have been stung
two more times since then, and each time it was 100% my fault.
I found that just reaching into the tank and grabbing an overturned
rock could yield a hiding lionfish. I can tell you from experience
that you don't want this to happen twice in your lifetime,
and you definitely don't want it to happen 3 times in 12 years!
So my advice is, "don't get stung!" Pay ultimate
respect to these fish at all times, and whenever you perform
any task in your tank, know where your lionfish are at all
times and be wary of them.
Sting... What To Do
a lionfish or scorpionfish ever stings you, the very
first thing to do is immerse the wound site in hot,
non-scalding water (110-113°F) for 20 to 30 minutes,
or until the pain subsides. According to Michaels (1998),
applying rapid heat using a hair dryer will also work.
The key point is heat; lionfish venom contains many
heat labile proteins, and heat will denature these venom
proteins, preventing them from spreading in the bloodstream
and decreasing the severity of their effects. Do not
use boiling hot water; the burn resulting from boiling
water will often be worse than the lionfish sting. The
most frequent symptoms of a lionfish sting are pain
and swelling. However, a few people may have an allergic
reaction to lionfish venom and should be cautious if
the pain and swelling get worse over a few hours. More
detailed information on envenomation may be found in
James Fatherree's article located here
in this issue.
Another wonderful dwarf lionfish Dendriochrius barberi.
This uncommon dwarf fuzzy lionfish makes a great little
display animal. Readily identified by its glowing red
eyes (unlike most Dendrochirus brachypterus that
possess blue eyes), this species requires the exact
same husbandry as its common Dwarf fuzzy brother. Photo
courtesy of Chris Smallridge (T-T-Trigger).
Often considered the ultimate
showpiece in a fish-only tank or as a novelty in a reef tank,
lionfish have established a place in our home aquariums. The
different sized species allow any hobbyist to care for a lionfish
in almost any sized tank, and to sense the mystical "coolness"
of lionfish. Owning a lionfish entails certain responsibilities,
and these can be met by following a few key steps to success:
provide a proper varied diet, compatible tankmates, and good
water quality. It is also important to respect these fish
at all times and be aware where they are when placing one's
hands in the tank. Once you've decided to commit to and care
for a lionfish properly, you'll be rewarded with the thrill
of seeing one of the oceans top predators in action. These
fish are long-lived and take on a dog-like personality; the
ultimate "Rover" armed with venom.
Talk about a rare lionfish... this is the Ambon lionfish,
a furry lion which utilizes its "fur' to hide amongst
the plant life. Fortunately, this rare lion never makes
it into the hobby. Photo courtesy of Jeff Rosenfeld
Shown here is Neosebastes entaxis, another rare
lionfish. These lionfish are found only in waters off
of Japan and are seldom collected for the U.S. Photo
courtesy of H. Uchiyama (http://www4.justnet.ne.jp).