Bloodfin Tetras Behavior

[fishy pat]

I recently set up an aquarium (26 gallon hex) and stocked it with six bloodfin tetras. One died the night after I put them in there. He acted kind of lethargic in the bag when I brought him home from the store, so I'm not sure that he was quite right when he was purchased. The other fish have been in the aquarium for two weeks and seem to be okay except for one strange behavior. One of the tetras likes to hang out near the surface of the tank while the other four hide under plants and driftwood at the bottom. If one of them comes out, the fish near the surface will chase them until they go back into hiding. When I feed them, the one at the top will chase all of the other fish into hiding and then head to the top to eat the flakes. When the flakes start to break into smaller pieces from him eating them, the others will all swarm out and eat the smaller pieces as they drift towards the bottom of the tank. Then, they will head back into hiding. The only time they deviate from this behavior is when all five get scared and school up during water changes. Is this behavior normal?

 

[Kelly-Jo]

It sounds like you have one aggressive fish that is bullying the others into hiding. There are a few ways you can improve this problem. Firstly, add more plants/decor or move current decor around to break up the line of sight so that the fish have less of a chance to be in direct contact with each other. Another possible suggestion is to increase the shoal size if this would be an option with your tank size/stocking. If problems persist, you may have to return the aggressive individual.

 

[fluttermoth]

It does sound like normal behaviour; most shoaling fish have one 'dominant' one that will boss the others around.

I'm more worried that this is a very new tank; did you cycle it at all before you added fish and are you monitoring your ammonia and nitrite levels?

 

[fishy pat]

Before I was born, my great grandfather had a tropical fish store that he ran out of his basement, and my Dad helped him when he was a kid. When I was a kid, my Dad got me started on keeping fish. Unfortunately, I haven't kept fish in several years due to losing all of my aquariums when the house I used to live in was flooded by a nearby river. My Mom found one of my old aquariums from my childhood in her basement and gave it to me a couple of weeks ago, which is what the Bloodfins are in. We always cycled the tanks with fish in the tank, and I didn't realize that you could do it otherwise until I read this forum. That's why I bought the bloodfins. I have cycled tanks with black skirt tetras and zebra danios in the past, and I wanted to choose something different that would still be a hardy fish. I am testing the water twice a day and doing water changes accordingly.

That brings up another question, though, when I test my tap water that has not been in my aquarium, it is coming up with .1 ammonia and .5 nitrites. Consequently, I cannot get my aquarium to zero ammonia or nitrites with water changes, I can only keep it at .1 and .5. Do you have any suggestions as to how I can get rid of the ammonia and nitrites? I don't want to put any ammonia remover products in the aquarium because I want it to be able to cycle.

 

[fluttermoth]

I honestly wouldn't worry about levels of ammonia and nitrite as low as that. Once your filter has cycled it will get rid of that in no time

I too am a newcomer to fishless cycling; I have done it in the past, but with fish food instead of the proper ammonia you can get now. That was 20 odd years ago; everyone thought I'd gone quite mad!