Opaline gouramis are beautiful hardy fishes that make excellent additions to the community tank. One of the characteristics that makes these fish unusual is that they tend to develop personalities and may also exhibit an awareness of their owners.
Like many species of aquarium fish, the opaline gourami is known by several other names. One of the most common alternate names for these fish is the marbled gourami, inspired by the rippled silver and blue coloration exhibited by these fish. Opaline gouramis are actually a color variant of the blue or three-spot gourami, so it can sometimes be found under these names. If you are looking for these fish online or in your local pet store, it may help to be familiar with the alternate names.
Like three-spot gouramis, opaline gouramis are a very hardy species and are not fussy when it comes to tank conditions. Because these fish can grow up to 5 inches in size, and because males of the species can become aggressive and territorial, they should not be kept in tanks smaller than 20 gallons in capacity. The ideal water temperature for an opaline gourami tank is between 72 and 82 degrees Fahrenheit, and the pH should be maintained around 6.0 to 8.0.
Because opaline gouramis are a tropical species, they require a warm, stable tank temperature. To maintain stable tank temperature you will need to invest in a quality aquarium heater with an adjustable thermostat. Filtration is an important aspect in maintaining a healthy opaline gourami tank, but your filter should not be too powerful. Opaline gouramis may be bothered by strong currents, so select a filter with a gentle flow rate. These fish do not have any specific requirements for tank lighting, so select your tank lighting based on the requirements of other fish or live plants in the tank.
Opaline gouramis are omnivores and will accept both plant- and meat-based foods. To ensure that your gouramis get all the nutrients they need, offer them a staple diet of high-quality tropical flakes or pellets supplemented with a variety of live and frozen foods. You may also offer your gouramis freeze-dried bloodworms and tubifex worms along with algae flakes and fresh vegetables. Gouramis are eager eaters, but don't overfeed them; overfeeding can result in the build-up of detritus in the tank, which can have a negative impact on water quality.
These fish are fairly peaceful by nature and can thus be kept in a community tank with other community species. Because these fish grow fairly large, and because males of the species can be aggressive, opaline gouramis are best paired with more robust tank mates like barbs, loaches, larger tetras and other gouramis. Be wary of keeping these fish with small or timid species because opaline gouramis may intimidate smaller fish and out-compete them for food. Avoid keeping more than one male of this species in the tank together unless it is a very large tank and you can provide plenty of hiding places.
Katherine Barrington has written on a variety of topics, from arts and crafts to pets, health and do-it-yourself projects. She has a Bachelor of Arts in English with a creative writing concentration from Marietta College.