How Do You Tell Is A Beta Is Likely To Be Aggressive?

[Jeremy180]

That is, before purchasing it?
I was thinking of maybe slowly moving my fingertip along the edge of the cup and seeing how aggressive a response I would get?
Like, Ideally a beta would either look curious, but not flaring it's gills or fins, or either swim away without appearing too fearful?
I'm basically looking for ways to tell before buying if the beta will be one of those more tolerant individuals that can adapt to a peaceful 29 gallon community.
 
My lfs has a good return policy, but I don't want to subject a fish to unnecessary stress like that if I can help it.
 

 

[Ch4rlie]

Do you mean a Betta Splendens?
 
Don't think a fingertip would show if its agressive or not, i think one of the best ways is to get a mirror and get the betta to see the reflection and see if he flares up, hard to do that if in a cup/container that does not have transparent glass.
 
Anyway, Bettas in general do not tend not to do that well in community tanks, they do best in a tank by itself with perhaps snails and even shrimps if it tolerates them. Minimum size of a 5 gallons filtered and heated tank would be best with some choice broad leafed plants like perhaps anubias. java fern or suchlike.
 
Of course you can get a betta sorority tank, all females, minimum of 5 bettas, but these need to be monitored for aggressiveness and can be tricky to keep.

 

[Jeremy180]

NVM, I just read on another forum that there is a danger of a beta eating anything smaller than a full grown glowlight tetra, and I'm planning on stocking fish less than half that size.

 

[Ch4rlie]

Not so sure if Bettas will eat small fish, but certainly small shrimps could be on the menu for Bettas.

 

[RainboWBacoN420]

Testing the personality of a Betta in the store in that tiny little cup is difficult since they're probably super stressed out and scared. I believe Bettas should always be kept in a solitary tank for themselves. Even though many have successfully kept bettas in community tanks, it's a really big gamble. I mean besides the betta being aggressive, the other can too, like nip his fins because they're so long, it could entice other fish to nip. 

 

[Byron]

As several have noted, Betta splendens (the common Siamese Fighting Fish or "Betta") is not a community fish.  There are those who say it works, but this is the exception, and frankly there could be negative issues promoting "compatibility" anyway.  The inherent behaviour of this fish, which one must assume will be likely to exhibit itself, does not make it considerable for community aquaria.
 
As for determining a fish's behaviour, this is next to impossible, though the environment in which the fish is placed in the store tank may cause it to behave specifically.  Individual fish can also be very different; accented behaviours (such as increased aggression), or the opposite (withdrawal and wasting away) can be induced by the environment being inappropriate, whether it be tank size, parameters, aquascape, other fish, etc.
 
I had a Betta many, many years ago, at a time when I knew next to nothing about most fish, and in a 20g tank he easily ate neon tetras.
 
Byron.

 

[Far_King]

I'm in full agreement with Byron.
 
A good few months back now I had a Betta in a 25 litre with some Panda Cories.  He always used to leave them well alone and just mind his own business.  One day this changed, he just got it into his head that he no longer wanted the Cories in his space and started to chase and nip them.  Fortunately I had another tank to move my Pandas into.  Credit to Byron, he advised me this was likely to happen.
 
Now my Betta shares his tank with a few Assassin snails and nothing else, I even moved the Cherry Shrimp he'd shown no interest in, just in case.  I'd not place any other fish in with a Betta now, no matter how placid it seems.  His good behaviour went on for months until suddenly changing, so there's no way you can tell from behaviour in a shop as to how the Betta will behave in the future.

 

[Ch4rlie]

I had a Betta many, many years ago, at a time when I knew next to nothing about most fish, and in a 20g tank he easily ate neon tetras.

 
This is an interesting point for me.
 
In the years I have been in this hobby, I have never heard of a Betta eating small fish that fits in its mouth. Of course, I have never kept a Betta simply for the fact I have shrimps in all my tanks and always thought the temptation to eat these shrimps for a Betta would be hard to resist, I never once thought about the predation on small fish for Betta.
 
This does make much more sense for me if these were wild caught or perhaps wild bred Bettas having more of a stronger instinct to have predary intention towards small or young fish species
 
Is this an inherent behaviour in most Betta Splendens whether wild or tank bred or is does this just depends on the temperment of the individual Betta?

 

[Byron]

 

I had a Betta many, many years ago, at a time when I knew next to nothing about most fish, and in a 20g tank he easily ate neon tetras.

 
This is an interesting point for me.
 
In the years I have been in this hobby, I have never heard of a Betta eating small fish that fits in its mouth. Of course, I have never kept a Betta simply for the fact I have shrimps in all my tanks and always thought the temptation to eat these shrimps for a Betta would be hard to resist, I never once thought about the predation on small fish for Betta.
 
This does make much more sense for me if these were wild caught or perhaps wild bred Bettas having more of a stronger instinct to have predary intention towards small or young fish species
 
Is this an inherent behaviour in most Betta Splendens whether wild or tank bred or is does this just depends on the temperment of the individual Betta?
 

 
First, it is not a predatory issue, but one of aggression.  The Betta sold in stores has been bred to be highly aggressive, hence it is commonly called "fighting fish."  This is not a predatory instinct that has been encouraged by breeders, but the pugnacious, aggressive nature which is natural in the fish and is being heightened by breeders.
 
It is well known that colourful fish seem to bring this instinct out more, and neons are certainly colourful.  The Betta when forced into a small space (any aquarium will be "small" to the fish) with fish that naturally enflame its aggressive behaviours will react accordingly.  But it has nothing to do with being predatory.  Betta, like gourami, have a strong sense of territory, and the fish is unlikely to tolerate other fish that it perceives as threats or invaders of its territory.
 
Byron.

 

[Ch4rlie]

Ah, that makes a lot of sense, and is almost obvious now that you have pointed these points out.
 
This is what makes this hobby so interesting, all these different facets and behaviour that can be brought out in just about any specie of fish can be down to simply the tank sizes and set up as well as other variables.
 
Thank you for these interesting posts about Betta Splendens 

 

[dgwebster]

Just thought I would throw in, I had a corner tank, roughly 9 gallon in size, which was a moderately planted tank housing a single male betta splenden and 6 african dwarf frogs.
 
never a single problem between them. Rocky (the betta) had the best personality i've ever seen in a fish. would follow me around the room, from one side of the tank to another and get what I would term "excited" when I came home from work (feed time hahaha)

 

[sabrinah]

The best way to check betta temperament before purchasing is to place two unfamiliar betta cups next to each other until you find a betta that does not flare at other fish. Then test to see if he flares at his own reflection. There is such a thing as a peaceful betta and they are perfectly capable of living with other fish if provided with the right environment. The tank must be at least 10 gallons and heavily planted. Any tank mates must be peaceful (meaning they will not bite your betta's delicate fins), and either not colorful or be fast swimmers. If other fish in the tank are bright or have flowing fins the betta may mistake it for another male. Ghost shrimp make great tank mates (just make sure you aren't being sold macro shrimp by mistake, because that's an awful situation) because they are dull in color, larger, and don't attract much attention. In many cases red cherry shrimp are a poor choice because they are tiny and brightly colored. It is sometimes said that a betta is more aggressive towards anything the same color as him (meaning a red betta is more likely to tear apart red shrimp than a blue betta is). It's also important to have the tank mates established in the tank before you put your betta in, and to give them at least half an hour with the lights off to adjust to one another. Most bettas prefer to spend time at the top or middle of the tank sitting on leaves or a betta hammock, so tank mates that prefer the bottom of the tank are best. 
 
If you want a ton of really great information check out bettafish.com. It is full of betta enthusiasts who know everything there possibly is to know about these delightful fish. 

 

[Far_King]

I'd have to disagree with some of that statement I'm afraid.
 
My Betta lived fine with Panda Cories, Red Cherry Shrimp and Otos for almost a year without taking any notice of them whatsoever.
 
Then one day, I noticed him taking an interest in the Pandas.  Then chasing and attacking them.  There was no reasoning behind his change in behaviour, it just changed, so I can't see that putting two betta in cups next to each other will have any bearing on their future behaviour, only their current behaviour.