Dying Tiger Barbs

[ZCaudill]

I have a 20 gallon tank and introduced 5 Tiger Barbs two days ago, the only other fish in the tank are three cory cats that have been in there since it was set up.

Two days after introducing the Tiger barbs three have died. This tank was setup in august. I have done two 25% percent water changes since the first barb died and the water seems fine. Within parameters for Tiger barbs to live. I’m not sure what to do other than treat with melafix that I have on the way.

Any advice would be appreciated.

 

[Colin_T]

Hi and welcome to the forum

Can you post some pictures of the fish and a picture of the entire tank?
What symptoms do the fish have when they are dying?

What is the ammonia, nitrite, nitrate and pH in numbers?

What sort of filter is on the tank?
How often and how do you clean the filter?

What are the tank dimensions (length x width x height)?

How often do you normally do water changes and how much do you change?
Do you gravel clean the substrate when you do a water change?
Do you dechlorinate the new water before adding it to the aquarium?

 

[ZCaudill]

Reply

I typically change 20% weekly

The tank is 24 long x 12 wide x 16 tall

Filter is just the basic hang on one that came with the tank, and I changed the filter the day before introducing the Tiger barbs.

The first fish slowly lost his ability to control his depth with his body downward and started floating near the top of the tank, he barely swam and finally turned over before completely passing away.

The second had the same issues and passed away in the same way.

I do clean gravel when I do water changes and I have one live plant in the tank.

The third seem fine but when I came back to the take had just passed away while I was gone and was sitting at the bottom.

pH between 7.0 and 6.5
Nitrites 0
Nitrates <10

My testing methods are not the best currently so these numbers are not 100% but close.

I always dechlorinate when I change water.

 

[Colin_T]

Any idea what the ammonia level is?

When you say you changed the filter the day before you added the fish, what did you do?

If you have filter pads/ cartridges and replace them, you get rid of the beneficial filter bacteria living in them and can get ammonia or nitrite readings. Ammonia will kill fish very quickly. Ammonia is less of an issue if the pH is below 7.0.

Normally you wash the filter pads/ cartridges in a bucket of tank water and re-use the pads. Tip the bucket of dirty water on the lawn.

You can put sponges in the filter instead of using filter pads and sponges get cleaned the same way and last for years. Just look for a sponge for any brand of filter and get a slightly bigger sponge than the filter pad. Then cut it down to size with a pr of scissors.

Until you can get some pictures, I would do a 75% water change and gravel clean the substrate every day until we work out what is going on. If there's a water quality issue or disease in the water, the big water changes will dilute it and help keep the fish alive a bit longer.

You should also contact the pet shop where you got the fish from and ask if the remaining fish have been ok. Let them know you have lost most of the ones you bought and they might give you a store credit or replace the fish. If they do offer you replacement fish, don't get them until we work out what is wrong. If you add more fish, they could die to.

 

[ZCaudill]

I want to take the fish back and get more because I’m sure only 2 Tiger barbs are stressed I need more with them, but I also don’t want more fish to die because of something to do with my tank.

They have actually been coming out more and swimming around since the last water change before they were hiding a lot.

Why would this situation not affect the Cory’s but kill the Tiger barbs.

Also I have API Stress Zyme+ if that would help anything.

I just turned off the top light and only have back lighting on and the two remaining barbs came out and actually ate some food I put in. Maybe the large hood light is stressing them out.

 

[Colin_T]

You need a picture on the back of the tank to make the fish feel more comfortable. You can buy aquarium backings form any pet shop or online, or use some coloured card, newspaper or a plastic bin liner. Just tape it to the outside on the back.

Turn the light down or off for a few days and it might help them feel a little more comfortable. Add some floating plants can also help shade the tank. You can use plastic plants and let them float or get real plants like Water Sprite.

 

[ZCaudill]

Ammonia test

Went and got ammonia test kit, looks like 0.

 

[Colin_T]

The ammonia is fine.

 

[ZCaudill]

I purchased a new filter Fluval U2, from what I researched my plan is to leave the old filter in while the new filter starts cycling.

I’m not quite sure what a good amount of time would be for that to take?

Any advice on steps I should take. My remaining Tiger barbs are still alive. Been changing water and monitoring ammonia levels. All 3 of my Cory’s are still alive as well.

Also do I need the bubble wall. It noisy and I’ve read certain post that say that bubbles aren’t always necessary.

 

[Jacky12]

My best guess is you bought a sick group of fish. I’ve been told by pet store employees many fish arrive in tinted water used to sedate them during transport and many begin dying immediately. This can happen even though the fish appeared active and looked healthy at the time of purchase.

 

[Colin_T]

If you add a second filter it needs to be in the tank for about 6 weeks for it to get the beneficial filter bacteria. However, it will only develop some good bacteria and the rest will be in the original filter.

You need some aeration/ surface turbulence to keep the oxygen levels up and carbon dioxide levels down. An airstone works well but a filter outlet spraying across the surface can also do the job.

If the remaining fish are well, monitor them over the next month and if no more die during that time, then get some more.