The Labyrinth Fishes: Part I
The
Gouramis
by
Jennifer Wilkinson, CAS
Originally published in The Calquarium Volume 41, Number 11.
Aquarticles
We recently purchased some baby pearl gouramis. Although we have
kept these fish before, it has been quite a
while, and I had forgot how interesting it is to watch them. With this renewed interest, I
began to do some
research. So here are some of my findings.
The characteristic that distinguishes these fish from the rest is
that they have a labyrinth. The labyrinth is an
air-filled breathing cavity, located under the gill covers. The labyrinth fishes can often
be seen going to the surface
of the water to take in fresh air. This makes it possible for these fish to survive waters
that don't carry much
oxygen.
Trichogaster trichopterus
There are many forms of this species of gourami. They come in the
blue three-spot, the blue opaline (which has
wavy darker blue lines running vertically on the body), and the gold-brown variety. The
males are slimmer and
have a longer, pointed dorsal fill and can reach a length of 15cm. The females' fins are
slightly shorter and
rounder, and they have a total body length of 13cm.
These fish come from all of Indo-China except Burma, and from
Indonesia east of Sumba and to the north-east as
far as the Philippines. They are found in ponds, rice fields, lakes drainage canals and in
rivers. They prefer planted
areas and will even withstand brackish waters.
These fish are a hardy aquarium fish, as they will take just about
any kind of water with a temperature of 24C.
They will also eat just about everything that is fed. They will fit nicely into a
community tank, as they won't bother
any of the other inhabitants. They need a fairly large aquarium, but I have kept them in a
120-liter community.
The males on occasion can become ornery towards the females, and will fight with other
males, by locking lips
and shaking or jumping. It is best to only keep one male with several females in a
well-planted tank.
The three-spot gourami is one of the easiest of the labyrinth
fishes to breed. The breeding tank should be at least
60 cm on one side, with a temperature of 28C. The water level should be lowered to about
half of the tank
volume. Shut off any filtration or air. The air or filtration will break up the male's
bubble nest. There should also
be some hiding places for the female. The male displays for the female by swimming in
front and around her with
his fins spread wide. When she is ready to mate, she will mouth him along the body. Then
the male wraps himself
around her and the eggs are released. The eggs float up into the bubble nest or are placed
in the bubble nest by
the male. The bubble nest is usually under a leaf or something floating at the top of the
aquarium.
I moved a pair of the three-spot gouramis into a 120-liter aquarium
by themselves. The water level was just
under half full. There were some plastic plants for the female to hide behind to get away
from the male if she
wanted to. A piece of Styrofoam was left floating on the top. After three days I checked
to see if I could see
anything. There was a bubble nest of sorts but it wasn't very big: there were really just
a few bubbles here and
there. On closer inspection though I found hatched fry under the Styrofoam. These fish are
big producers: there
were over 300 eggs from that spawn. The book says they can be continuous spawners,
spawning every few
days, and I do believe this as they spawned again shortly thereafter.
Trichogaster leeri
The pearl gourami is one of the most beautiful of all the gouramis.
The female can reach a total length of 10cm,
while the males can reach a total length of 12cm. Older males have a longer pointed dorsal
fin and sometimes
have lengthened rays on the anal fin. The body and unpaired fins of both sexes have
beautiful mosaic pearls that
shine in the aquarium lights. The males when in full color display bright orange to deep
red on the throat and
breast area.
They come from South Borneo, Sumatra, and from the south of the
Malay Peninsula. These gouramis prefer the
shallow, warm, and overgrown parts of standing or slowly flowing waters.
The pearl gourami is a very peaceful fish, making it easy to keep.
The water should be fairly soft and the
temperature 27C. They prefer a medium-sized to large aquarium that is well planted. They
are good in a quiet
community tank. I am currently housing three in a 240-liter community which consists of
three flying fox, six
scissor-tailed rasboras, six red tail rasboras, seven harlequin rasboras, a pair of
America flag fish, and one
porthole live bearer. They seem to eat anything that I feed, however they seem to have a
preference for green
flakes and Grindal worms. They eat mostly at the top of the aquarium but have been seen
eating off the bottom as
well.
Breeding the pearl gourami relatively easy. The breeding aquarium
should be 80 cm in length or larger, with some
floating and anchored plants. The aquarium should be filled about half full with no air or
filtration. The temperature
should be 29C. The male begins by making a small bubble nest that he enlarges over time.
When the female is
ready to spawn, she forces herself into the flank of the male until he wraps himself
around her. The female is
turned upside down and the eggs are released. The male then chases the female away and
begins collecting the
eggs that are floating up toward the bubble nest. As many as 2000 eggs can be laid in one
spawn. When the fry
become free swimming the male should be removed from the aquarium. The female should be
removed right after
spawning.
Trichogaster pectoralis
The snake-skin gourami has a greyish or yellowish color with
vertical lines or bands running down the body.
Males get to a total length of 20 cm, while the females only reach a total length of 18
cm. The males have a
distinctly longer dorsal fin.
The original range of these fish is limited to the lowlands crossed
by the lower courses of the Menam and
Mekong rivers. As a food fish they were introduced into other areas.
These gouramis should be housed in a 185-liter aquarium or larger.
They are quite peaceful for their size but I
would not include them in a community with small fish. They like a well-planted aquarium,
with a temperature of
25C, with no special water requirements. These fish will eat anything.
Breeding these fish is quite easily accomplished. Put a pair in a
large aquarium with plants, no filtration or aeration
and leave undisturbed for a few days. The temperature should be 29C. The males are bubble
nest builders. They
are productive spawners, laying 3000 to 5000 eggs per spawn.
I have chosen not to keep this gourami because of its size.
Trichogaster microlepis
The moonlight gouramis are a silvery color, sometimes with a bluish
shimmer. The male has orange pelvic
thread-fins while the females are clear or sometimes yellowish. The male's dorsal fin is
usually broader and
longer. They usually have a black spot on the end of the tail, just before the tail fill
begins. The total length of the
male is 18 cm while the female only gets a total length of 15 cm.
They come from Cambodia and central Thailand, where they inhabit
standing or slowly flowing heavily planted
waters. This is a food fish in its native land.
Although they are a rather large fish, they can go in a large
community aquarium. They look best with other
colorful fish. They will eat dry and live foods with out a problem. They don't have any
special water
requirements.
The moonlight gouramis are moderately easy to breed, meaning they
are not as easy as some, but they are
possible to spawn in the aquarium. Set up a well-conditioned pair in an aquarium of at
least 80cm length. The
tank should be well planted and include floating plants as well. The male will build a
large plant and bubble nest.
The males can be very aggressive, so they must be watched to make sure the female doesn't
get to beat up. They
spawn under the bubble nest, with the eggs floating up to the nest. These fish often have
very large spawns. The
female should be removed right after spawning, the male should be removed when the fry go
free swimming.
Although these fish are quite peaceful, except at breeding time,
they still get quite large. I don't think I will include
them in my community aquaria.
Helostoma temmincki
The kissing gourami has an oval-shaped, laterally-compressed body
and a pointed snout. There is a Gary green
form, supposedly the wild form, and the pink form, which is all I have ever seen in the
fish stores. They can reach
a total length of 20cm, but are usually smaller in the aquarium. It is very difficult to
tell the sexes apart.
They come from central and southern Thailand, the Malay Peninsula,
Sumatra, Java, and Borneo. They live in
slowly moving waters. They have also been found in ponds, lakes, puddles, and flooded land
with lush
vegetation. This is another food fish.
These fish will not make a good community aquarium resident. They
can not compete for food and will starve.
They eat only small foods, preferably from the water's surface. They will eat some dry
foods. They require a
large aquarium that should be 80cm long or larger, with some hardy plants such as Java
fern. Tender plants will
take a beating. The optimal temperature for these fish is 26C.
Breeding these fish is very difficult. To condition the pair, feed
with Artemia nauplii and other small crustaceans.
Introduce the pair into a large tank with a temperature of 29C, and lots of floating
plants. The kissing gourami
does not build a bubble nest. They lock lips (kiss) before the mating, which occurs in
various places in the
aquarium. They can lay up to 10,000 eggs per spawn. The eggs are sticky and will stick to
the plants, and will
also float to the surface. A kissing gourami will eat its own spawn, so the eggs or the
parents should be removed.
This is another gourami that I choose not to keep. It gets too big,
and I would be very concerned at being able to
provide a good enough diet.
Osphromenus goramy
The giant gourami is a brown to bluish Gary in color. They can
reach a total length of 100 cm. In the aquarium
hobby they are much smaller, but are still a very large fish. The anal and dorsal fins on
the male are pointed.
The fish originally came from the Indonesian-Malayan area. They
live in ponds, streams, ditches and large rivers.
They can take some brackish waters. They are also a food fish.
These fish are not fussy about their water conditions but a
temperature of 25C should be maintained. The young
fish will grow quickly and will eat anything. These fish are tolerant of their own kind,
and would make a good
community fish with other fish of this size. Not recommended for the regular community
tank with tetras and
rasboras.
The giant gourami is a very difficult fish to breed. The spawns
contain 500 to 2000 eggs that float to the surface
and are looked after by the male.
This is another gourami that is commonly available, but I choose
not to acquire. For one thing this is a big ugly
fish. (my opinion only) It's not suitable for my aquarium communities.
Colisa labiosa
In thick-lipped gouramis the males are larger than the females. The
males get to 9 cm, while the females only get
to 8 cm. The males also have a pointed dorsal fin that can extend to the end of the tail
fin. The males of this
species have a rounded anal fin, like the females. Both sexes have black and white chin
bands running from their
eyes. The pelvic fins and the edges of the anal fin are yellow to orange in color. The
females can have a band
running the length of the body, but usually the individual spots that this band is made up
of can be seen. These
markings can also be seen on some of the males of this species.
The thick-lipped gouramis come from Burma, where they live in
rivers.
These are hardy fish and can be put into a well-planted community
aquarium. They are not fussy and will eat all
kinds of fish foods. They are also not fussy as to their water conditions, as long as
regular water changes are
done and the water is kept clean. They can be quite shy and may hide in the plants.
The thick-lipped gourami is an easy fish to breed. They will often
spawn right in the community aquarium. To
spawn these fish, place a conditioned pair in a 60-liter tank that is thickly planted.
This aquarium should have a
temperature of 28C. The female will use the plants as a hiding place to escape the male's
advances. The male will
build a small bubble nest. They spawn in typical gourami fashion, under the bubble nest.
The spawn will consist of
400 to 600 eggs that will float up into the bubble nest. The female should be removed
after the spawning is
completed. The male should be removed after the eggs hatch and before the fry become free
swimming.
This fish sounds interesting to me. Now I will have to start
searching for a healthy pair or a few young fry. They
stay fairly small and will fit nicely into one of my communities.
Colisa lalia
The dwarf gourami has a reddish orange body with diagonal turquoise
blue bands. The fins have the same
colouring. The males are larger than females at a length of 6 cm, and are the more
colorful of the two. The female
is only 5 cm, and she is quite pale in color, sometimes even looking silver with a
slightly blue tinge. The male
becomes very brightly colored at spawning time. There are also many other color strains
available, but I like the
above mentioned.
These fish come from India.
They are great community aquarium fish, as long as their tank mates
are not extra lively. (Larger barbs not
recommended). They are not fussy eaters, as they will eat anything being fed. They do seem
to like live foods, as
well as the prepared mixtures. They are also not particularly fussy about the water they
are kept in, as long as it is
kept clean with regular water changes. The ideal water temperature is 26C, as they do not
like cool or cold
water.
This is another fish that is easy to breed. It will often spawn in
the community aquarium. The book says the spawn
may be moved to another tank. I think this may be just a little risky. To have them spawn
in a separate tank,
place a well-conditioned pair into a 40-liter or 60-liter, thickly planted aquarium. The
female will use the plants to
hide from the male's (sometimes aggressive) advances. There should also be floating plants
for the male to build
his bubble nest under. They spawn in typical gourami fashion with the male wrapping
himself around the female
under the bubble nest. The spawn can consist of 300 to 700 eggs. After spawning is
completed, the female
should be removed. The male will tend the spawn until the fry become free swimming, then
he too should be
removed.
This is another gourami that I would add to one of my community
tanks. They are quite colorful and stay small. I
think they will fit in quite nicely.
Colisa sota
In the honey gourami the female is larger than the male. The female
gets to a total length of 4.5 cm, while the male
gets to a total length of 4 cm. The males are a beautiful bright orange color, and have a
black throat and abdomen
that extends into the front part of the anal fin. Most of the dorsal fin is bright yellow.
The males are not quite as
bright when out of spawning condition. The females are plain, with the body being slightly
tinged brownish
orange, with a silvery fluorescent glow.
The natural range of these fish is north-eastern India, Assam, and
Bangladesh.
The honey gourami is well suited to a community aquarium, although
it can become territorial, especially at
spawning time. They prefer an aquarium with some thickly planted areas but also like some
open swimming
areas. They are not fussy as to water requirements. They do prefer clean water, with
regular water changes. They
will eat just about everything being fed to the community tank.
These fish are moderately easy to breed, meaning a little more
difficult that Colisa lalia but not impossible. Set
up a well-conditioned pair in a 40-liter aquarium with lots of floating plants, no air
stone or filter (They may need
to be conditioned separately). The male will build a large bubble nest. The eggs will
float up into the bubble nest,
but the male may move them. However he will guard over them until they go free swimming,
which is when he
should be removed. The female should be removed right after spawning. The eggs are clear
at first, then turn
yellow, then black before they hatch.
I haven't quite made up my mind if this is a gourami that I would
want to add to one of my community aquaria.
It's a little more difficult to keep and breed. Perhaps at a later date, if I have some
success keeping the easier
ones. The good thing about this fish is that it stays a small size.
Trichopsis vittatus
It is difficult to tell the difference between the sexes of the
croaking gourami. The males have more color with a
red edge to its longer anal fin. The males get to a total length of 7 cm, while the
females get to a total length of 6.5
cm.
These gouramis come from eastern India, Thailand, Vietnam,
Malaysia, and Indonesia. They live in standing or
slowly moving waters with lots of plant growth.
The croaking gourami is a good community tank inhabitant. They are
peaceful and will get along with tank mates
that are not too big. They can even put up with polluted waters although I would never
recommend trying this.
They will accept dry foods, however live foods should also be a part of their diet. If
more that one male is placed
in an aquarium, they will circle each other and make a croaking noise, hence the name.
This behaviour never
causes harm to the fish.
Breeding these fish is fairly easy. Set up a well-conditioned pair
up in a 40-liter to 60-liter aquarium with some
floating plants. No air stone or filtration is needed. A clay flowerpot on its side will
serve as a bubble nest building
site. Sometimes the bubble nest is build at the surface under the floating plants. The
male wraps himself around
the female and the eggs sink to the bottom. The male quickly scoops up the eggs and places
them into the bubble
nest. Usually there are around 200 eggs per spawn. In small aquaria the female should be
removed after
spawning. In larger aquaria, she will indirectly care for the spawn by guarding the
outside areas of the nest. If the
male chose a nest site that was not near the surface of the water, he will move the nest
to the surface as soon as
the fry hatch.
This sounds like a very interesting gourami to keep. It may not be
as colorful as some, but their behaviour caught
my attention. This fish stays small, and sounds like it would fit nicely into one of my
community aquaria. Now
where can I find a pair or a bunch of nice healthy young fry?
Sphaerichthys osphromenoides
In the chocolate gouramis the males are larger with
better-developed and somewhat pointed dorsal fins. The male
has a total length of 6cm, while the female has a total length of 5.5cm. These fish are a
dark brown color with
three or four stripes. They have a forked caudal fin.
They come from the southern part of Malay Peninsula, Sumatra, and
the southern part of Borneo. They are found
in weed-grown puddles and shallow ditches, and in slow flowing streams, often in dark
brown water.
These fish must be kept in a species aquarium. They WILL NOT
SURVIVE in a community tank for very long.
They require soft acidic water with a pH of 6, is very clean and slightly moving, and with
a temperature of 28C.
The aquarium should be 100 liters or larger with some peat added. Black water extract
could also be used.
Regular water changes are a must. Live foods are a must, but they may eat some prepared
foods as well.
The chocolate gourami is very difficult to breed, but if kept under
the above-mentioned conditions, they should
spawn readily. The females are mouth brooders. The male will help with the eggs, which are
laid on the bottom
by spitting them over to her. The young are released from the female's mouth in 17 to 19
days. At the time they
are released they are already a chocolate color.
This is another gourami that sounds fascinating to keep. But do I
really want to set up a species aquarium right
now? No, I don't think so. Perhaps at some future date.
In conclusion to The Gouramis, I would like to say that this family
of fish for the most part sounds very
interesting to keep in the aquarium. I personally feel that I don't want to keep the food
fishes. For one thing they
get way too big for any of the aquaria that I own. The other thing is I don't find most of
the larger fish pretty to
look at.
I didn't really mention how to raise the fry so I guess I should
mention that here. Most gourami fry grow very
slowly. Allow at least four to six months to raise them to selling size. They all require
infusoria for a first food, then
will eat baby brine shrimp. Then most will graduate on to the prepared foods and larger
live foods. Culling is a
must as there are usually too many fry for the hobbyist to raise properly. However if one
has a lot of aquaria, they
can be spread out. Over crowding will only cause poor growth and stunted fish. Not a
pretty sight.
Now I'm off in search of the gouramis that I chose out of this
list. I hope my research will be helpful to other
hobbyist interested in this family of fish.
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