Opaline Gourami: Care, Tank Mates, Size & Lifespan

Opaline gourami are beautiful freshwater fish that are slightly overlooked in the aquarium scene. And with so many other gouramis to choose from, it’s understandable.

But there’s a lot to like about this species!

These fish are gorgeous, easy to care for, and rather active (this is a very fun species to spectate). This guide will teach you everything you need to know about opaline gourami care, so you’ll be ready to get some for yourself!

Species Summary

The opaline gourami (Trichopodus trichopterus) is a beginner-friendly freshwater fish with a lot to offer aquarists of any skill level. Sometimes called the marbled gourami, this fish is not naturally occurring. It’s a product of selective breeding and is considered a distinct variation of the famous three-spot gourami.

While this particular species doesn’t appear in the wild, its ancestors are usually found in Southeast Asia. These tropical fish hail from wetlands and marshes throughout India, Cambodia, Malaysia, the Philippines, and more.

Author Note: Like all gouramis, these opaline beauties are not like your average fish! They have quirky personalities and distinct behaviors that make them a joy to care for (and will make them stand out in a community tank).

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In terms of body shape and silhouette, opaline gouramis are straight from the usual mold. They have the same iconic gourami profile, which is oval-shaped. The head is slightly pointed near the mouth, but most of the fish is noticeably ovate.

The recognizable shape is primarily due to the anal fin. It is on the bottom of the fish and stretches from the ray-finned pectoral fins down to the caudal fork. Of course, there are also needle-like ventral fins as you would expect.

An opaline gourami looking for food

These fins are delicate and almost look like antennae. They’re touch-sensitive and play a big part in the fish’s navigation.

As for color, opaline gouramis are pretty eye-catching. The base color is silvery blue. However, splotches of deep cobalt blue create a unique marbling effect. The intensity of this pattern varies from one specimen to the next.

Breeders typically aim to have the most vivid coloration possible, leading to some genuinely awe-inspiring fish!

Author Note: Males and females look very similar. The only main difference between the two is the dorsal fins. On males, the dorsal fin is long and pointed. Meanwhile, it’s more stubby and rounded on the females.

Average Opaline Gourami Size

The average opaline gourami size is around six inches in length when fully grown. 

Most fish are considered “mature” when they reach about three inches. At that point, they are capable of breeding (more on that later). They usually continue to grow a bit until they reach the upper end of the size spectrum.

Author Note: The two main factors that will influence the size of these fish is genetics and the quality of care they receive. Do your part by being a responsible owner, and always do your homework when researching potential sellers!


In good living conditions, the typical opaline gourami lifespan is between four and six years. They may live slightly longer if you’re lucky, but those instances are few and far between.

As you probably know, there’s no way to guarantee a fish’s life span. There’s a degree of chance and genetic prosperity at play. Not only that, but the level of care you provide will have a big impact on your opaline gourami’s life expectancy.

Opaline Gourami Care

For the most part, gouramis are fantastic fish for beginners because their needs are relatively straightforward. The opaline gourami is no different. 

But with that being said, opaline gourami care still requires you to be familiar with some essential requirements. These freshwater fish have preferences and basic needs just like any species.

Here are some need-to-know tips on how to give the opaline gourami the best life possible.

Tank Size

For adult opaline gouramis, it’s best to stick with aquariums that can hold 35 gallons of water or more. You can keep juveniles in tanks as small as 20 gallons. But as they get bigger, you’ll need to upgrade to accommodate their playful behavior and vigorous swimming habits.

Author Note: A 35-gallon aquarium is adequate for a single fish or a very small group. If you plan on creating a larger community environment, it’s always best to go bigger. 

Water Parameters

Usually, the best course of action is to look to a fish’s natural habitat for guidance about water parameters. Because opaline gouramis aren’t naturally occurring, you have to look at their closest relatives: the three-spot gourami.

These fish live in warm and humid environments. They’re also used to shallow waters filled with plants. As a result, the habitat tends to be slightly acidic and moderately hard.

Fortunately, opaline gouramis are also hardy! They can adapt well to a wide range of parameters, giving you a little leeway in setting up the tank.

  • Water temperature: 73°F to 82°F
  • pH levels: 6.0 to 8.8 (near neutral is best)
  • Water hardness: 5 to 35 dGH

Because maintaining proper water parameters is such an important part of opaline gourami care, you need to make sure you have a reliable water test kit handy. This will allow you to keep tabs on the state of your tank and make adjustments when necessary (before problems arise).

What To Put Inside Their Tank

Opaline gouramis aren’t too picky as far as decor comes. The goal here is to add items that work with their looks and lifestyle!

One opaline gourami exploring the inside of the tank

Starting with the substrate, go with something dark. Opaline gouramis move throughout the water column, so they don’t care much about the exact material. Whether you choose pebbles or fine sand, a darker color will make the gorgeous blue tones and marbling effect pop!

Next, you can add some plants and modest decorations here and there. These fish are relatively confident, but it’s still a good idea to have some plants for shelter whenever they need solace. However, you don’t have to go wild and cover the entire tank with dense vegetation.

Author Note: In fact, you may fare better keeping most of the tank open. These fish are active swimmers. Not only that, but they’re labyrinth fish!

They belong to a unique class of fish that can breathe atmospheric air. Opaline gouramis must have access to the surface of the water for breathing, so do your best to keep plant growth manageable.

Common Potential Diseases

Opaline gouramis are at the whims of the environment they’re in. Insufficient care and a poorly maintained tank could make these fish suffer from a wide range of diseases.

They’re susceptible to all the usual health problems. However, some conditions seem to be more prevalent than others.

Ich and hole-in-the-head disease are quite common in opaline gouramis. Parasitic infections cause both conditions. With Ich, white spots start to form all over the body. For hole-in-the-head disease, you might see deep pits around the lateral line and head.

Fortunately, these diseases are treatable. If you notice something wrong, you must act fast! Ich can spread throughout the closed aquarium, while hole-in-the-head disease often leads to bacterial infections. Quarantine your fish the moment you notice symptoms and provide treatment.

Author Note: The best way to avoid diseases is to maintain the tank and water conditions. Test regularly and perform 25 percent water changes every two weeks or so. This will help keep your fish healthy and overall stress levels low.

Food & Diet

The opaline gourami is a hungry omnivore that will consume just about anything you provide. They do best on a balanced diet of algae-based foods and protein-filled snacks.

As a primary source of dietary nutrients, provide commercial flakes or pellets. Look for balanced formulas that focus on color vibrancy for the best results. You can provide two small meals a day to keep your fish happy and healthy.

A few times a week, try offering up some high-protein foods! Opaline gouramis are pretty fond of bloodworms, brine shrimp, and other popular aquarium foods.

Author Note: Interestingly enough, opaline gouramis will also look for any hydra. Hydra is a tiny pest microorganism. Most freshwater fish actually can’t eat hydra, so opaline gouramis can be quite helpful in this regard!

In addition to high-protein foods, you can try blanched vegetables like peas. Opaline gouramis aren’t picky, so feel free to experiment and see what they like!

Behavior & Temperament

Opaline gouramis are generally peaceful freshwater fish. They can do well as community fish with other species.

However, this particular gourami variety is a little more territorial than most. Males often butt heads if kept in a tank that’s too small for the pairing. Adult fish may bully smaller ones as well.

Opaline gourami in a freshwater aquarium

Ultimately, temperament and aggressive behavior varies from one fish to the next. Keeping an eye on them in a community tank is paramount. Most won’t have any issues, but you should always watch them and address troublesome behavior.

Throughout the day, opaline gouramis are a joy to watch! As mentioned earlier, these fish can breathe atmospheric air. They have a special labyrinth organ. You can spot them sipping air from the surface every once in a while.

When they’re not doing that, you can find these fish playfully swimming and exploring. They’re surprisingly active, so there’s always a show to enjoy!

Tank Mates

Opaline gouramis can be semi-aggressive depending on the tank mates and environment.

The best way to keep the peace is to pair these fish with non-aggressive species of the same size. Avoid anything significantly smaller than the gourami. It’ll quickly become dinner!

It’s important to steer clear of known fin-nippers, too. Those delicate ventral fins on the opaline gourami can become targets for smaller bullies.

Not sure where to start with an opaline gourami community tank? Try these tank mates on for size:


Breeding opaline gouramis is a fairly easy and rewarding experience. The process is an interesting one!

These fish build bubble nests to lay their eggs. Males also exhibit some protective behavior over the eggs, which is not common in the fish kingdom. Even still, it’s a good idea to provide a separate breeding tank to maximize fry survival rates.

The breeding tank should be shallow. Only five to six inches of depth is all you need. Use peat filtration to condition the water and install some sponge filters to keep the fry safe once they hatch.

Keep the water temperature warm. Around 80 degrees is ideal for initiating spawning. To trigger the breeding process, you can also provide plenty of high-protein snacks.

The female will start to swell with eggs. In response, the male will build the bubble nest. When they’re ready, the fish will spawn below the nest. As she releases the eggs, they’ll float up to the nest to incubate.

You can remove the female after she lays the eggs. Males will guard them for the next few days before they hatch. After the fry emerges, they will feed on the egg sac for another couple of days. Once they’re free-swimming, you can remove the adult male and feed the babies infusoria or powdered food.


Opaline gourami care is really simple once you understand the basic needs of this species. With the exception of some rare aggressive behavior, you shouldn’t have any trouble keeping these fish happy and healthy.

We hope you found this guide useful and give this lovely species a chance! They’re one of our favorites.

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