I have 2 females in a 1 meter tank, well planted, with rock caves, and these two are very territorial, seems to me as territorial as the males should be.
I once bought an adult male blue gourami to add to my 125 liter tank, in which I already had an assortment of gouramis (1 male and 2 females dwarfs, 1 snakeskin female, 1 pearl female and 1 gold female, all of them full grown). As soon as I put him in the tank, he started terrorizing everybody. Even though the snakeskin gourami was much bigger than him, she was no match. I could hear her slamming into the glass as she swam full tilt trying to escape him. After two hours of that, I could not stand it anymore and removed the male. I took him back to the dealer the next day and got a full grown blue female. Far from being a bully, she gets picked on by the gold female.
I have four of these beautiful fish. Two males and 2 females. Although they are a little territorial, I have yet to see aggression, and I've had them for about 6 months! The females are MUCH smaller than the males, and they both staked out territory in plants, while the males cruise near the cave. I would recommend them with other quick fish who are a decent size.
I obviously got lucky when buying this fish, and found an extremely rare temperament in my male. He is actually a great surrogate mother to my baby gouramies, and will viciously protect the fry from the female and other gouramies after hatching. I have not seen any aggression towards any other fish or frog in my aquarium aside from this. I DO NOT, however, recommend these fish for inexperienced fish keepers, as I have had others that were territorial to the point that they killed several of my gouramies.
I have 3 varieties of the 3 Spot Gouramis in a 450 liter community tank: a male Opaline, a female Lavender, and a female regular 3-Spot. The females are far more aggressive than my sweet male. Even when I had other male 3 Spots in the tank, the females were always the ones bickering. Two of mine, in fact, disliked each other so much I caught them engaging in Kissing Gourami behaviour: they'd circle and chase each other, then lock lips and have a little tugging match. Never heard of 3 Spots doing this. Must say that they were great with my other fish, including shy Pearl Gouramis, Betta splendens, and Guppies.
I have a total of 6 gouramis in my 100 litre tank. I have 2 gold, 2 three spot and 2 dwarfs. I feel that the impression of these fish being rather aggressive is not true in my case. Occasionally they do seem to pick on each other, however I find they seem to leave other varieties of gouramis and other fish alone. They are a beaufiful fish when at a larger size and I recommend them to anyone with an Asian tropical tank.
I have one blue gourami, one opaline gourami, and one golden gourami, all of which are females. At first I had the opaline alone. She was very jovial, playful and peaceful with her other tank mates. When I added the other two, who were smaller than she at the time, she hassled them a little, but once her rank was recognized, she did not bother the others much. A couple months later Ich struck its deadly hands into my tank. Many of my fish died, but all the labyrinth fish survived, the gouramis without even a blemish. However, in the process of cleaning the tank, the hierarchy between the three females was overturned and the most picked on before is now dominant. She is not as lenient as the former head honcho and is constantly attacking the other two gouramis. She body slams, engages in jaw wrestling, and chases the others all around blowing bubbles from her gills all the while. In my experience, many, especially dwarf Gouramis, will stress themselves to a point beyond saving without places to hide. However, the larger gouramis tend to pick on each other a lot then settle out their differences given enough territory. If they continue fighting, the usual cause is lack of space or hiding. All in all, these are beautiful, extremely hardy fish which each have unique personalities. They love their people, love to be fed, and do all sorts of cute things like feel other fish with their feelers and blow bubbles from their gills.
I have been keeping 2 three spot Gouramis for over a year now. They were a mature pair rescued by my LFS after being found dumped in a pool of water by the road. I named them Clarice and Bert. They are bright blue in colour with the classic markings. Bert is a very dominant male and is always bullying Clarice. They are both fully grown, but have shown no interest in spawing. They make a great addiction to my 90 L community tank. They readily eat from my fingers and are very placid. I really like them as they are a low maintenance fish that look pretty good in my tank.
In my experience gouramis tend to be one of those pet fish: that is, fish that interact with their human viewers instead of ignoring them or hiding. Most labyrinth fish I've kept do this, and so when I got my first 3-spot I was pleased to find out that she did too.
My female 3-spot can tell apart the various members of the household (in terms of most likely to feed the fish), almost always shows interest in anyone watching her (drifts to the near side and taps the glass with her feelers), will hand-feed (even from young children, and she learned to do this quickly), and shows moderate interest in tank maintenance (instead of hiding). When my female betta was alive, the gourami showed a lot of (non aggressive) interest in her - more interest than the betta wanted! She's the sole labyrinth fish now, so everything is hers: she ignores the otos and at feeding time chases the dithers if I don't hand-feed her.
An adult or patient older child would need to teach the fish to hand-feed: until they're used to it you need to move slowly, and young kids tend to jerk their hands. But after a month or so of hand-feeding the gourami my 5-year-old nephew had no problems feeding her by hand, it tickles jerks and all. (Just remember: ALWAYS supervise young children around an aquarium!)
Now, they ARE motivated to do this by food, not affection. People who don't ever feed the fish will be given the shifty eyeball by the fish, if not outright ignored. BUT, if you take the time to tame this fish, then the 3-spot gourami is a fish that actually WILL come to the front of the tank to greet you when you come home. :)
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