
The Labyrinth Fishes, Part I
The Gouramis
by Jennifer Wilkinson, CAS
originally published in The Calquarium Volume 41, Number 11, July 1999
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 northeast 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 grayish 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 silverish 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 gray 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 gray 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 coloring. 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 northeastern 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 behavior 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 behavior 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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