Dwarf gouramis are one of the two most widely sold gouramis (the other being the three-spot gourami), and virtually every aquarium shop will sell them. They are generally peaceful, accept flake food readily, and are not fussy about water chemistry (though soft, acid water is best). However, despite being widely sold and seemingly easy to keep, they are in fact not easy fish at all. As with any pet animal, it pays to do your research first.

Latin name

Currently, the Latin name for these fish is Colisa lalia. You will see other names though, such as Polyacanthus lalius and Trichogaster lalius.

Identifying dwarf gouramis

In their normal form, males are characterised by oblique red and blue stripes, while females are plain silver. There are a variety of artificial forms as well, including some that may be hybrids with other gourami species. These varieties include all-blue forms (sometimes called neon, blue, or powder blue dwarf gouramis) and ones with a red body instead of the stripes (sometimes called flame, red, or sunset dwarf gouramis). Females of all these artificial varieties are more or less plain silver and similar to the wild-type fish.

So what's the problem with dwarf gouramis?

Put simply, these fish are astonishingly prone to mysterious bacterial infections. Once the fish begin to get sick, death is more or less inevitable. The symptoms are typically:

1 - Lethargy
2 - Loss of appetite
3 - Appearance of bloody patches (sores) on the skin
4 - Death

Is this the same as Fish TB?

Though the external symptoms are similar to Fish TB, the problem with dwarf gouramis is caused by a completely different bacterium. Fish TB being primarily an issue with marine fish, not freshwater ones.

Fish TB is known to infect humans (albeit very rarely), but the dwarf gourami sickness, whatever it is, poses no known risk to humans. However, it is a good idea to wash your hands after handling sick fish, or for that matter anytime after you have worked in your aquarium.

But I thought gouramis were hardy?

In the wild state, they are. But dwarf gouramis are bred on farms, where antibiotics have been used freely to minimise losses. Once shipped to the retailer, the dwarf gouramis no longer receive antibiotic medication, and the internal bacteria can then start to cause problems. Inbreeding for colour varieties has probably lowered their intrinsic hardiness as well.

What can I do?

Above all observe two rules: only buy fish from tanks containing healthy specimens, Never, ever buy a dwarf gourami from a tank where there are sick, lethargic, or otherwise unhealthy-looking fish.

Secondly, quarantine your fish rigourously. Dwarf gouramis should be quarantined before being added to the community tank, and any new gouramis (of any species) should be quarantined before being added to a tank with dwarf gouramis in it.

Anything else?

The bacteria seem to be opportunistic, so improving conditions generally helps prevent problems. Specifically, keep the water clean, and don't overstock the tank. Feed the fish on a varied diet, and use a good quality flake food as a staple. Dwarf gouramis like the water warm (25-28C, 77-82F); cooler conditions depress its immune system. Ideally, use soft, acid water, but whatever the water chemistry, perform frequent water changes. Do not combine with tankmates liable to stress the fish, such as tiger barbs, territorial cichlids, and so on. The less stressed the gouramis are, the healthier they are going to be.

Social behaviour

Like other gouramis, males can be aggressive towards females. Ideally, keep multiple females to every one male so that any aggression is spread out. However, since these fish are normally sold as pairs, you may not have that option. In this case, keep the tank thickly planted and provide lots of caves for the female to hide in. Do not keep a pair in a tank less than 60 cm in length (approx. 20 US gal.). Thanks to Fillet 'O' Fish for this.

Cheers,

Neale

This post has been edited by nmonks: Aug 13 2006, 03:10 PM

Nice Article Neale Should be pinned.

I felt maybe you should have written a little more about keeping these in pairs, and how the female should be given plenty of plant cover to escape the males 'over affection' and chasing therefore stressing her out.

This post has been edited by Fillet 'O' Fish: Aug 12 2006, 01:38 PM

Excellent! Definately should be pinned. Problems with dwarf gouramies, as you've said, seem to crop up on the board all the time and this could make a huge difference for many prospective dwarf owners.

There are only a few little things I want to add.

First, just to avoid any misunderstandings, the powder blue/red flame etc color morphs that were mentioned are not hybrids but simply selectively bred varieties. People may read that sentence and think they are hybrids. As you know, of course, there are some fish sold as Colisa lalia that may well be hybrids so mentioning that there is still a good idea. I just think it may be better to make the point clearly seperate - a simple re-wording is all I'm suggesting . BTW, the hybrids are typicaly with honey gouramies (Colisa chuna/sota). I appreciate this first suggestion is a major nitpick

Another little thing I'd like to point out is that people should learn the scientific name for the dwarf gourami before going and buying one as the common names can be confusing. they are often named according to color but these names are not standardised so you might find yourself looking at a 'rainbow' gourami or a 'dwarf honey' gourami. Note that the names used for some dwarf color morphs are very similar to the names used for other Colisa species (eg: the honey example I just gave).

In terms of the diseases - the symptoms not only resemble fish TB, dwarfs also often carry this disease. A hollowed out appearance can often be the first symptom - as can open sores as described. Fish TB can have a devastating effect on a tank and, arguably (it seems to be the marine form that's realy problematic), can affect people too. This further highlights the importance of quarantine.

It may also be an idea to add bloating/pineconing of scales (ie: dropsy) on the list. dropsy is a symptom, not an actual disease and often presents itself, alongside lethardy and loss of appetite in stressed dwarf gouramies. It also signifies an internal bacterial infection.

In terms of choosing your dwarf (or any gourami for that matter) it's important to also avoid fish that are constantly gasping at the surface or always 'resting' on the bottom. It's normal for a dwarf to go up for air every few minutes and this is healthy behaviour but sticking to it, or worse, staying on the bottom, are often the first signs of trouble at the LFS.

When it comes to keeping dwarfs, I'm realy against keeping them as pairs though I appreciate the difficulty that may be involved in obtaining a trio. As has been clearly said, these fish are very prone to disease and any form of stress (including fluctuating water conditions or bullying from other fish) can trigger serious illness so it's important to try to minimise stress as much as possible - keeping pairs tends to have the opposite effect though heavily planting and providing a large tank certainly helps.

This is the last point (I promise ) - the reason dwarf gouramies are so fragile isn't limmited to their treatment with antibiotics that means that even weaker fish, that would otherwise have died, are bred and produce equaly unhealthy offspring that can't survive under normal tank conditions - their inbreeding is also an issue and the way they are mass-bred for superficial traits (ie: color - not health) doesn't help either. Leading on from this, when you buy dwarf gouramies, it's best to only buy apparently healthy individuals that have been at the LFS for at least a week (two is even better). As harsh as it might sound, this allows the weaker individuals to die before you come along and buy the hardier, surviving, fish.

That's all I know I ramble on quite a bit lol Oh, BTW, there's a little typo that you should correct in the link for Colisa lalia. You are missing the 'a' in Colisa. I'm not fussy with this sort of thing - it's just in this case it's more important

I'd like to comment on a couple of things...

"Secondly, quarantine your fish rigourously. Dwarf gouramis should be quarantined before being added to the community tank, and any new gouramis (of any species) should be quarantined before being added to a tank with dwarf gouramis in it."

I dissagree with this. I'v never quarantined any of my gouramis before adding them to my tank. And never had a problem with disease in the whole time i'v had them... 6 years now.


"Social behaviour

Like other gouramis, males can be aggressive towards females. Ideally, keep multiple females to every one male so that any aggression is spread out. However, since these fish are normally sold as pairs, you may not have that option. In this case, keep the tank thickly planted and provide lots of caves for the female to hide in. Do not keep a pair in a tank less than 60 cm in length (approx. 20 US gal.). Thanks to Fillet 'O' Fish for this."

I dissagree with this too. All my gouramis are bought in pairs, one male and one female. Again i'v never had a problem in 6 years with aggression nor hiding females... they all get on super.

Got a headache from reading too much today lol... so will read again tomorrow and probably reply again to other points that i missed

Fair enough - but I have to ask - are you keeping dwarf gouramies or another species?
Also, what do you mean when you say 'you've kept/are keeping pairs'? If you are talking about a group of 4 (2 pairs) or more, that's not a valid point. Keeping a group of gouramies is very different to keeping a single male/female pair (or 2 individuals of any sex for that matter) as a hierarchical pecking order isn't established in the way it would be so one fish will invariably end up bullying the other (either the male bullies the female or the larger the smaller - in larger groups a complex order is established so that aggression and attention from males is split and therefore diluted).
I don't doubt that you can keep pairs of dwarfs together though - but I avoid doing it myself because of the stress issue (that can cause serious problems with dwarfs).
Anyway, this point is one you can argue from both sides on. For one, the tank conditions play a vital role in determining how dwarfs react towards one another so the issue is far mroe complex than it appears on the surface. A large tank can support more fish and will acomodate a pair better than a small one. Similarly, higher temps. (which are what dwarf gouramies do best at however) will encourage more activity and may cause males to be aggressive. Similarly, fish in good condition are more likely to be interested in breeding and that can trigger more chasing of the female(s) and mroe aggression. Even the food the fish get and how often they are fed will have some effect on their behaviour and on their stress levels - as will the current, decor, lighting and general water quality. You also need to consider the tankmates - these can serve both as a distraction or as a trigger for aggression. Regardless of all this though, I stand by the idea that keeping pairs is not ideal. it's far simpler, as a guideline, to keep trios or groups of one sex only.

However, the quarantine point is not one I think should be argued over - it is always better to quarantine new fish - whether they are gouramies or not - to avoid introducing disease to an established tank. Anyone who has encountered 'neon tetra disease', fish TB or has kept particularly fragile (or expensive ) fish will agree on this. Quarantining fish doesn't take as much effort as you might at first think and it certainly prevents a lot of deaths and saves time (and money) later on down the line.

so is it okay to keep just one dwarf ?

Yes.

Cheers,

Neale

woooooooo i love the lil fish they look so gurd. Getting one on sunday

have my gouramis and there lurvely setlling in nicely along with 2 new clown loach (to get rid of snails)

Not trying to be harsh but the fact you haven't had a problem with disease just means you got lucky when you purchased the fish that was disease free. You can't really know 100% if the fish you purchased are free of disease hence the quarantine.

I think maybe a picture should be included.

I'm realtively new to keeping dwraf gouramis but thought I'd post a pic-
Two males bickering over hierarchy (they stopped like two seconds after I took the pic, usually they prefer to harrass the bristlenose catty)



Emma

I found the comments on this forum very useful as I am slowly but surely losing all my gouramis, and am close to pulling my hair out for an answer!!!

I used to have 6 - 1 dwarf red, 1 dwarf, 2 gold and 2 opaline, and have now just got the 2 opalines left.

It all started about 2 months ago when the dwarf red mysteriously gained an open sore above its head. I went down to my fish shop and was given a course of Myxazin to try (5 days). This had no effect and over the course of a few days more sores appeared, it lost interest in food and stayed hidden in amongst the rocks before finally dying. Then all seemed well for a few weeks until one of the gold gouramis contracted the same illness. Slowly but surely they have all had the same symptoms and last night I finally lost the dwarf after keeping him for some five months.

I have always regularly carried out partial water changes and change the pads in the filters regularly, and had begun to wonder if it was parasites from the frozen bloodworm that I occassionally give them.

I wont add any more fish until I am certain that the opalines are going to be ok, but am now considering keeping some other types of tropical fish in the future (I only went with the gouramis as when I just had a few they were attacking any other type of fish.

Any comments would be helpful!!! Thanks

Sorry to be the bearer of bad news!

Opaline gouramis are a variety of Trichogaster trichopterus. They are, if not immune, then certainly not sensitive to the Dwarf Gourami Disease. Apart from the aggressiveness of the male specimens, these are among the most trouble-free fish in the hobby, and generally a sound investment. The same holds for the blue and yellow versions of this species.

Nothing cures Dwarf Gourami Disease. The best you can do is provide optimal conditions and hope the fish gets better itself. Since the problem is, at least partially, viral, even antibiotics won't work. Personally, I'd recommend painlessly destroying sick fish.

No, the disease comes from the fish farms. No-one really knows how or why.

My advice is avoid dwarf gouramis. Go with Colisa labiosus or Colisa fasciata instead -- they look similar, do well in communities, and are only a little bigger.

Hope this helps, Neale

wow... i just bought 1 dwarf flame, and 1 dwarf neon blue yesterday... i thought they were perfect, but this forums is really making me nervous... i dont want these kinds of issues.... just reading it makes me sad... but i dont know where to get the colisa labiosus or colisa fasciata... i bought mine from an average petco, but they'd been there several weeks and seem healthy... they're in a 10g with only one other fish, a green emerald cory...

now when you say painlessly destroy the sick fish (just in case anything does happen), how would one go about doing this?
whats a good, hardy, really pretty fish that could go in a 10g with only a couple other inhabitants? i need colorful, and pretty... like the dwarf gouramis