New Factor on my Congo Tetras?

[cupofjoel]

My congo tetras used to school like crazy. Now they don't.

I just recently added 3 electric blue acaras.

Now my tetras are scattered, explore the bottom of the tank more frequently and single tetras will go off on their own.

1) Are my congo tetras more comfortable now that the tank has been their home for over 2 weeks?
2) Are the acaras a new factor and what factor do they play?
3) Other ideas?

thanks!

 

[PheonixKingZ]

I think that they are a little rattled that there are new fish introduced. Are the acaras showing any signs of aggression?

 

[cupofjoel]

I think that they are a little rattled that there are new fish introduced. Are the acaras showing any signs of aggression?

No the acaras are being peaceful. I've been monitoring them and they are getting along fine.

 

[utahfish]

Acaras can be pretty aggresive and im sure congos long flowing fins attract attention.
Other than that im not sure.

 

[PheonixKingZ]

No the acaras are being peaceful. I've been monitoring them and they are getting along fine.

Acaras can be pretty aggresive and im sure congos long flowing fins attract attention.
Other than that im not sure.

The aggression of the acaras are the only thing I could think of.

@cupofjoel, make sure you monitor the acaras closely. If you say they are showing no aggression, the Congos should settle back in soon.

 

[cupofjoel]

The aggression of the acaras are the only thing I could think of.

@cupofjoel, make sure you monitor the acaras closely. If you say they are showing no aggression, the Congos should settle back in soon.

I've read that blue acaras tend to be aggressive toward their own species.

Nonetheless, they are leaving the tetras alone, but will run into each other during feeding time, which is to be expected.

 

[PheonixKingZ]

I've read that blue acaras tend to be aggressive toward their own species.

Nonetheless, they are leaving the tetras alone, but will run into each other during feeding time, which is to be expected.

Ok. Just keep a close eye on them. Have a backup plan, just incase this doesn't work out...

 

[cupofjoel]

Ok. Just keep a close eye on them. Have a backup plan, just incase this doesn't work out...

My only other guess is that there are more male congo tetras than females? Could that affect the school?

 

[PheonixKingZ]

My only other guess is that there are more male congo tetras than females? Could that affect the school?

Yes, that could be it. It is recommended to keep Congo Tetras in a 2-3:1 ratio. (Females:Males) Or, to keep an all Male school.

 

[cupofjoel]

Yes, that could be it. It is recommended to keep Congo Tetras in a 2-3:1 ratio. (Females:Males) Or, to keep an all Male school.

Yeah I bought a batch of 12 young ones so there was no way to control that. As they mature I'll be able to tell which ones are male and will try to adjust the numbers.

 

[cupofjoel]

Update: They are back to schooling and the blue acaras will sometimes join!

 

[Retired Viking]

I noticed with my tetras that after a few days they break up and do not school as much until there is a major change in the tank, (new fish, new item) then they are back to schooling. When I 1st set up my tetra tank I added a small shoal every week or two because I was doing a planted cycle. The 1st was red eyed tetra which after a few days stopped pretty much swimming together, I added a shoal of embers and everyone was back schooling for a few days, same thing happened when I added a shoal of neon. At the end it looked like the train station scene for the cartoon movie Zootopia. Eveyone back in the schools swimming around.

 

[Essjay]

Can I just clarify something.

Shoaling refers to fish species which live in hundreds or thousands in the wild. Their need to be in a group of the same species is programmed into their DNA which is why we should keep several of these species.
Schooling fish are shoaling fish which swim tightly together and move as one. Many marine fish behave like this, but there are not many freshwater fish which do. There are some freshwater species which swim together but most do it only when afraid, such as when first put in a tank, during water changes, a predatory fish in the same tank etc. When they are not afraid, they go their separate ways.

I do not know if congo tetras are schooling fish, but they are shoaling fish. But if they are not a schooling species but they are showing schooling behvaiour, they are not happy fish.

 

[PheonixKingZ]

Update: They are back to schooling and the blue acaras will sometimes join!

Good news.

 

[seangee]

This may not be good news!
As @essjay suggests there is a difference between shoaling and schooling species. Many people don't recognise this difference and use the terms interchangeably. I don't keep congos but most of my tetras only form a tight group when they are stressed or frightened, like when my cat tries to catch them through the glass . The fact that they initially "schooled" and after a couple of weeks relaxed enough that they were happy to explore on their own suggests that this may be the case with these. If this is the case it means they are being stressed by their tankmates.