Tiger Barb Behavior

[CatLover]

I used to have a school of 10 tiger barbs. This morning I woke up and found 3 dead - totally out of the blue. Nothing had changed. The only thing I saw different last night was that two of them seemed to be starting a fight with each other. I thought nothing of it, since they play with each other like that all the time.

Tonight I spent hours observing the remaining 7. There seems to be a pecking order, which I had noticed before. But I caught new behavior tonight. There is one barb in the group that seems to have assigned the job of terrorizing two others for some reason. I don't know if there is something wrong with these two, or if the rest of the group sense something wrong with them. The barb bites and rams the two outcasted barbs, one at a time. He bites mainly their head, and puts his mouth on their forehead and pushes them far away from the group. The submissive barbs always hurry back to the group, and the same barb chases them off again in the same manner. After it goes on long enough, the whole group will nip at the shunned barbs and chase them away. These two barbs have lost nearly all of their color, and act like they desperately want to be part of the group again, but the other barbs won't have it.

What in the world is going on? Is this just a harmless pecking order being put in line like with wolves, does it have something to do with breeding, is there something wrong with those 2 barbs that only the others can sense? Even after researching online, I'm totally stumped. Is it likely I'm going to wake up to two more dead fish? My tiger barbs are my fav

 

[CatLover]

Well, I didn't wake up to any dead fish, and those two barbs have fully gained their color back and are swimming with the school again. Thank goodness! I just hope they don't get singled out again.

 

[Grouchy]

I have 20 tiger barbs, all but five of them were raised from fry to adult status. One of the parents is still in the tank.

I have only noticed the situation you described once, there were two barbs that seemed shunned by the others. I isolated one in a hospital tank, it died about 7 days later, but it stayed hidden the entire time. The other remained in the tank as I tried removing a problematic barb (overly aggressive). I kept the other barb in isolation for a while. Eventually, one of the other males in the tank outgrew the problem barb and after two tries I was able to integrate everybody.

That was the only time I noticed segregation of one or more barbs.

I have noticed that at times some will go off in their own little world but come feeding time they are all swimming together happily.

Also, I think I can say there are "problematic" or "rogue" tiger barbs that are more prone to aggression despite numbers (low numbers or congestion due to high numbers). For example; you introduce a different species to the tank, there is a recognizable male and female that will always lead the abuse of the other fish, which will eventually interest the others leading to a swarm. The fish I isolated in the first situation was just mean, attacked everything including tugging at the tail of a pleco four times it's size.

First thing I would do is check levels, making sure ammonia, nitrates, etc. are tolerable. If water chemistry is acceptable for the tiger barbs then I would simply watch them for a while, make sure they aren't suffering from a disease. Things should sort themselves out, but if they don't you might have a sick fish or if it's just one fish doing all the violence try moving the one barb to it's own tank temporarily and see what happens with the rest of the group.

 

[sharbait]

I had eight green tiger barbs - I'm now down to four or five. Water chemistry is good and they don't look diseased. They don't bully the other fish or each other, in fact they seem the most placid fish in the tank. They're certainly scared of the red-tailed-black-shark.

When I've found them dead, my two dwarf gouramis were picking at the corpses. I'm wondering whether I have any plants toxic to tiger barbs. Or perhaps I have a psycho fish lurking in the tank...

 

[Tokis-Phoenix]

Tiger barbs are agressive fish by nature and will harrass each other amoungst other fish, if your barbs have suddenly become more agressive for their own good recently due to a changing of pecking orders i would re-arrange the decor of the tank, setting up clearly defined terotorys with open areas between densely planted areas and add a couple more tiger barbs- the more barbs you have the less chance of one barb being picked on too much there is, so when barbs start dying of over harrassment you should add more to the group instead of lowering their numbers, the extra numbers will not only make them feel more secure but by adding new fish the barbs will be forced to re-arrange their pecking orders depending on how dominant the new fish are- a changing of decor re-arrangment in the tank and making new hiding areas will also help pecking orders and give shelter to any barbs in distress .

 

[sharbait]

Thank you! It just so happens that I picked up some new ones yesterday, and rearranged the tank (only because a plant came loose!). That seems to have helped.