New tiger barb swimming diagonally and not socializing

[Pazda]

Hi, I recently got 5 tiger barbs and 5 zebra danios for my new 15gal tank. Everything was fine, the fish were happy but one tiger barb got caught in the filter and died, so we since tied some clean net to the end of it, and no more accidents have happened.
However, when I bought a new tiger barb, it has since been sitting in a corner, not socializing or anything, and it's swimming diagonally like this
| \ |
if the | |s are the aquarium corners and you're looking at the fish's front.

Is this because of the bladder problem? Should I try feeding him a crushed pea? The zebra danios also seem to 'tease' him a bit, but not excessively.
He occasionally goes to the other tiger barbs but only for a few moments before swimming back to his corner.

[CrunchyLeaf]

A lot of things can cause this type of behavior. The first information we will need to rule out some of the common problems is a history of your tank.
Did you cycle it before adding fish?
If so, how did you cycle it? Briefly describe your process.
What are the current parameters when you test the water? (Ammonia, nitrite and nitrate) post actual numbers.
What kind of filter is it?

My guess is that there is a bigger issue than just this one fish. Otherwise healthy fish don't often get sucked onto the filter intake. That fish was likely weakened by sickness or dead before it got sucked up on the filter.
Have you considered a larger tank? Tiger barbs are active schooling fish that get to be a decent size as adults. They arguably need a minimum tank size of 30 gallons, some others would say 55 gallons due to their very active nature. Your tank is severely overstocked and if you don't change your stocking or your tank size, this may just be the start of your problems.

[Pazda]

Well, it doesn't matter now that he's dead... three fish died from getting sucked into the filter, two even with a safety net. What can I do to fix this?
Yes, I cycled the tank.
I put the filter and water in, live plants, and everything else, let it all run for 3-4 weeks putting food in every 2 days, and tested the water until it was fine.
I'm not sure what kind of filter it is.

[Pazda]

never mind, found it: aqua-tech 5-15 power filter with bio-fiber biological filtration and EZ-change #1 filter cartridge

[rodm81]

Well, it doesn't matter now that he's dead... three fish died from getting sucked into the filter, two even with a safety net. What can I do to fix this?
Yes, I cycled the tank.
I put the filter and water in, live plants, and everything else, let it all run for 3-4 weeks putting food in every 2 days, and tested the water until it was fine.
I'm not sure what kind of filter it is.

Did u use a liquid test kit,test strips,or took water to your closest pet store? A fresh water test kit would be best. Did you get readings of ammoni=0, nitrites=0, and nitrates=20 ppm or lower? As far as the tiger barbs like crunchy leaf mentioned Tiger Barbs should be in minimum of 30. I had a species only Barb tank and those fellas are very active and used the entire tank to school.

[patrickriley2010]

off topic but my dad had a pond in our front yard with gold fish he redid the walls with new rocks and a month later i lifted one and there was a goldfish pinned down, he some how survived he swam crooked but eventually started swimming right thought it was amazing.

[Pazda]

bump. the water's getting bad since I can't have the filter on... how can i make sure no more fish die?

[genocidex]

if your fish are getting stuck to the inlet then you can add a sponge filter to it to stop them from getting stuck. turning off the filter is the worst thing you can do, hope your bb isnt dead

[Pazda]

I couldn't find one of those for my aqua-tech filter. Are there any homemade solutions?

[genocidex]

get an aquaclear filter sponge, cut a slit in the almost to the end leaving like a half inch. insert the inlet tube into the sponge. works well for my plants and my shrimp