Pls Help Asap Zebra Danio Attacking Other Danio?

Hhi, I had 2 danio in my tank originallty and I wamted more so that rhey xould school so last night I added 3 more, 2 long finned leopard and 1 more zebra. Today I woke up to my old zebra danios attacking the new ones and my othe old one dead with its tail nipped at. I think my old danio killed the other one and I think I'm going to have to return the old one, is there anything I can do?

 

Do you have any other fish in the tank other the danios? What are your water parameters?

 

What size tank? What is the entire stocking?

 

Hi,
It is normal for schooling species such as danios to nip at each other to establish a pecking order, but usually not until the point of death. When u found the danio dead, how badly was it damaged. I asked this because you could have brought a new disease with the new danios that could have killed the old danios. Did you notice any aggression between the old 2 danios? Watch the danios closely, and if things get out of hand, remove the bully, or just separate the.

 

Do you have any other fish in the tank other the danios? What are your water parameters?

Yes I have 8 long skirted tetras and 3 khulI loaches, and I hvae a 37 gal tank

What size tank? What is the entire stocking?

37 gal, 8 long skirted tetras and 3 khulI loaches other than the danios

Hi,
It is normal for schooling species such as danios to nip at each other to establish a pecking order, but usually not until the point of death. When u found the danio dead, how badly was it damaged. I asked this because you could have brought a new disease with the new danios that could have killed the old danios. Did you notice any aggression between the old 2 danios? Watch the danios closely, and if things get out of hand, remove the bully, or just separate the.

Its was pretty bad the tail was practically gone, and the 2 original danios were not aggressive at all toward each other berfore I added the new fish

 

Are you sure that it was the old danio that killed your fish. Could it have been the new additions, because I don't understand why the danio would get so aggressive

 

Whats your decor like? Is there enough plants or hiding spots? Plants break the vision of fish so it always helps when there's a bully.

Whats your water parameters

 

which one was nipped? The long fin ones?

I suggest getting at least 10 zebra danios to disperse any aggression.

KuhlI loaches are a shoaling fish so you should have at least 6