gourami experts??

[HillDog]

note: I have searched the web and cannot find anything saying smaller gouramis (~5 in) cannot be housed with snakeskin gouramis (~8-9 in)

I have a thriving 55 gallon tank several years old...

mostly peaceful fish: loaches, corydoras, ghost shrimp, danios, swordtails, plecos.

and some semi-aggressive fish: 1 gold, 1 platinum, 1 blue, 1 opaline gourami all females...

And I have been eyeing the bigger growing variety snakeskin gourami. From what little I have found on the internet, it is mostly non-aggressive in groups...

Would that mean adding a female snakeskin would be okay since I already have four other females that get along?
Or would the eventual size difference cause a commotion with bad outcomes for either my band of old gouramis or the snakeskin?

Thanks for any help

 

[M_surinamensis]

Behavioral predictions can sometimes be slightly tricky. I mention this because my response which follows needs a big neon sign on the front, blinking, in letters fifty feet high... explaining that it is based on what is likely rather than what is definite. ... and that I am not responsible if you read the post, decide to get a snakeskin gourami and it ends up killing everything else being kept in the tank, plus your dog and your next door neighbor.

Gourami aggression really falls into two categories.

They are opportunistic predators and will eat anything small enough to fit in their mouth, depending on the species of loach and danio- and the size of the ghost shrimp, this may be an issue for you with larger gourami species. I would not keep an adult snakeskin gourami with zebra danios or kuhli loaches because it'll probably end up eating them eventually.

The more worrying aggression when assembling a community tank is that which will sometimes be displayed towards other fish that are too large to consume, it is largely a result of the breeding behaviors of the group (pretty much the entire suborder actually, to varying degrees). The males will display territorial aggression towards other males of the same (or closely related or similarly shaped) species as a result of competition for mates. The males will also sometimes get rough with the females- territorial harem breeder behavior, he's displaying how strong and suitable he is as a mate. Both genders will also display egg and nest site guarding behaviors when breeding- and some element of that can bleed through to behavioral changes prompted by the animal's readiness to breed, regardless of the actual act.

In large environments this kind of aggression is not too much of a problem, because other fish will simply steer away from the one behaving aggressively. Tanks are obviously smaller than wild environments though and it is sometimes impossible for other fish to get far enough away to satisfy the territorial behaviors of the aggressive fish. This is especially true of males, but can also be inconvenient if a female decides the appropriate place to build a bubble nest (fertile eggs or not) is the center of the tank. Male gouramis tend to regard most tanks as being entirely their territory. Female gouramis are much less inclined towards aggression and tend to only get that way around a small area immediately surrounding their nesting site.

Additionally, the results of aggression can be different in different environments. The more fish the aggression is spread out between, the less impact it is likely to have on any single individual. So if the snakeskin (or any of your existing gouramis) begin to display aggressive behaviors and the tank contains a decent number of fish for them to spread their aggression among, chances are that no single individual will end up with much worse than a nipped fin or being chased away before another fish ends up stealing the aggressive individual's attention. This does not apply to male gouramis with other male gouramis, where their attention will remain tightly focused on their direct competition.

Given the nature of female gourami aggression, such as it is, it is also something that you can manipulate. If you see one building and defending a bubble nest, you can break up the nest and remove the point of focus for the territorial behaviors. If one is clearly swelling with roe and developing a more distinct ovipositor, you can make environmental changes that drop them out of breeding condition and shift their behavior away from the response set associated with breeding behaviors.

All of which means... it's probably fine to add a female. Keep an eye on it and be ready to respond to any visible signs of aggression, but as a species they are not really any more inclined towards overt displays of it than the other gourami species you are already keeping and familiar with. In fact, they tend to be a bit mellower as a rule of thumb, even when breeding.

The biggest issues that are likely to result would be a problem with the relative size if you happen to be keeping smaller species of danio or loach... and the larger maximum size of the snakeskins means that they are not mature until they are slightly larger, so sexing them as juveniles can be a bit trickier. Same indications as the species you currently keep, plus some sexual dimorphism when cycled to breed (fin color of the males), just... bigger adult size, so these indicators aren't as obvious and developed at smaller sizes. Best guess sexing without a magnifying glass requires them to be about an inch and a half or so- reliable sexing is easier at bigger sizes.

 

[HillDog]

Thanks! That's a lot of useful info! I have only had them try to spawn once but that was when I had a male in the tank. Since then they have stayed slimmer and non-aggressive except for the chase out of their immediate territory like you said. None of them have nipped fins so I figure they are doing fine. The loaches are "dojo" loaches, and I doubt extremely that even a nine inch gourami could fit them in his mouth, and they stay hidden for the most part. I do however have four small zebra danios... but they are very fast and have plenty of floating plants to hide in I would think. They also like the flowing water around the filter where the gouramis generally shy away from for the calmer four/fifths of the tank. I didn't think about the later sexual developemnt and sexing, but the ones at my lfs are already three and four inches so they should be okay!

PS, I would never hold it against you! Thanks A LOT for the advice!

 

[Krow]

I have a few gourami including one snakeskin in a tank with a pleco, corys, neons, rainbow sharks, african dwarf frog, and a huge angel fish and they are all fine, Ive never seen any signs of aggressiveness, and I see them all the time since they are in my room.