Identify your gourami species (recommended). The term gourami refers to an entire family of fish, including over 90 species. While many of the gourami species and varieties popular among aquarium hobbyists can be bred in the same conditions, this does not apply to every species. Ask an experienced fish breeder or biologist to examine your gouramis if you do not remember the name they were sold under.
- This guide is accurate for dwarf gouramis, pearl gouramis, kissing gouramis, blue (three spot) gouramis, and honey gouramis. Note that kissing gouramis may be more difficult to breed than the others, and require a larger tank.
- True gouramis and chocolate gouramis are especially difficult to care for and breed, and the process is not covered in this article. The chocolate gourami, and some other species, care for the eggs in a parent's mouth.
- If your gouramis do not belong to the species listed above, or if you are not certain of the species, you may still use this guide, but you may have a lower success rate or encounter unexpected difficulties.
- Gathering this type of food on your own increases the risk of passing on diseases to your fish, and is not recommended without the advice of a local expert.
- It may be easier to notice the change in size looking down from above.
- In some gourami species, females have a more rounded dorsal and anal fin (along the spine and near the anus), while the males have a more pointed one.
- Kissing gourami are difficult to identify by appearance. However, if two of the gourami are "kissing, " they likely belong to the same sex, and are fighting for dominance.
- If all your fish seem "swollen, " try withholding their food for three or four days. Overweight males may slim down during this time, while egg bearing females probably will not.
Part 2Setting up a Breeding Tank
- Select a tank of the appropriate size. For most gourami pairs, select a tank that can hold 10–20 gallons (40–80 liters) of water up to a six inches (15 cm) water level. This relatively small size and shallow water level actually encourages breeding and fry health, but it is not suitable for all species. Here are a few notable exceptions:
- Kissing gourami will only spawn in a large tank, at least 24 inches (60 cm) deep and at least 36 inches (91 cm) long.
- Pearl gourami can be bred in a tank with this water depth, but the tank should be at least 31 inches (80 cm) long.
- Blue, or three-spot, gourami can be bred in this tank size, but a somewhat larger tank will work as well. A larger tank may minimize stress and injury to the female.
- Species that grow more than 10 inches (25 cm) long, including the true gourami and giant gourami, may require much larger tanks. Consult an expert before attempting to breed these species, with the exception of the kissing gourami described above.
- Add gravel and anchored plants. Start by adding a thin layer of gravel at the bottom. Use this to anchor several plants, large enough for the female to hide behind if the male becomes aggressive. Leave some open area as well.
- Upturned clay pots and other common aquarium additions can also be added to create hiding spots.
- If putting rocks in the tank, be sure these are bought from an aquarium store, as rocks gathered in lakes and rivers may alter the pH of the water.
- Add floating plants or objects. Some species, such as the pearl gourami, create a "bubble nest" for the eggs on the underside of a floating plant. You may use actual floating plants, or cut a Styrofoam cup in half lengthwise and float it on the surface of the water. For species that do not build bubble nests, such as kissing gourami, you may wish to float a piece of lettuce instead, which will provide nutrients for the newly hatched fry.
- Do not cover more than 1/3 of the water surface, as gouramis need to take oxygen directly from the air as well as the water.
- Put a cover on the aquarium. Protect the air above the water level from cold drafts by attaching a lid to the aquarium. Make sure there is air between the lid and the water level, and that the lid contains holes to allow the passage of some air.
- While this is not necessary for adult gourami, young fry are highly susceptible to air temperature changes, and could die if the air becomes too cold.
- Use a sponge filter. Never use a filter or air stone that creates a current in a breeding tank, as the current can destroy eggs and young fry. Adults may not be willing to lay eggs unless the water is completely still.
- Adjust the temperature, pH, and nitrites if necessary. Use an aquarium test kit to monitor these attributes of the tank water for several days, before any fish are introduced. Prepare the tank with a "fishless cycle" to keep toxic nitrites and nitrates out of the water. Heat the tank to around 77–82ºF (25–28ºC), and adjust the pH to between 6.6 and 7.5. Lower pH by adding soft water, such as reverse osmosis water, and raise it by adding crushed limestone, coral, or other carbonate materials.
- Warning: Do not transfer fish between tanks with different temperatures. Instead, gradually increase the temperature of the tank after the breeding fish have been introduced.
- The temperature and pH ranges given here are a narrow band suitable for all the common gourami species mentioned at the beginning of this guide. If you have identified your gourami species, you may be able to search online for a broader range of acceptable conditions for that species.