strange barb behaviour

[Cavafish]

Hi. I have an 400l tank which among others houses 15 barbs, 5 tiger, 5 green tigers and 5 golden barbs. ( see sig below).

Can anyone she any light on some really unnerving behaviour of my barbs?

On returning from work I took a quick look around the tank and then fed the fishes their usual flake dinner. After about 3-4 minutes watching them eat, I noticed one of the stripey tiger barbs pointing down towards the gravel and twitching violently. All of its fins were flickering at a rapid rate, it was breathing fast and seemed to have no ability to steer itself but was drifting around the tank in a very distressed looking state. is what I thought!

I phoned my local store and they said that this was quite normal for tiger barbs and that the store fish do this all of the time after being fed!! (If I had seen it I wouldn't have bought them!) Thier swimbladders get upset due to the food in thier stomachs and this imbalance is what causes the trouble. No worries, it will sort itself.
The poor ole barb was still like it the next morning (16 hours later) but was ok by lunchtime by which time I couldn't even tell which fish it had been.

Has anyone come across this themselves or can give any extra info on this? I've been fortunate enough to have had no problems at all so far with my fish and this was horrible to watch, I don't want it happening again.

 

[drobbins27]

My barbs only do that at night when resting...weird...

 

[Lateral Line]

If only one did it, and it was a one off, not a regular occurance, I wouldn't worry about it. It is true that in the frenzy, fish can gulp to much air which makes them more buoyant so they nose down. They can also eat to much which can give similar symptoms.

What you can do if it becomes a regular thing is try soaking the flake in a glass of tank water before feeding, that way they will not gulp air at the surface, and any swelling of the food is already done.

 

[Cavafish]

Brilliant Lateral, thanks.

So far it has been a one off incident but the way my LFS spoke I have ben expecting it to happen again.
I tend to dunk flake below the surface as well as let it float as the two pearl gouramis in the tank are possessive of any floating food and can get stroppy. It also gives the sharks and foxes a chance as I have never seen them at the surface.

Thanks again

 

[Yenko]

My Tiger barbs do that too. If I overfeed they float like that for a while. It can also be a sign of water problems, so you should check your Nitrate and Nitrite levels.

 

[Cavafish]

Thanks Yenko.

SInce setting up the tank I have never recorded a nitrite reading. It has always been zero.

Nitrate has on occasions got as high as 50 but never for very long. I have never measured ammonia......

 

[Stryker]

If you have no or low nitrates in your water then it would suggest to me you either have some hungry plantlife in your tank. Or Have a problem with the bacteria that breaks down ammonia into nitrites or the bugs that take nitrite and turn it into nitrate.... either way I'd be making for my test kit to test ammonia and nitrite.