Weird Fin Nipping!

Hey everyone, so I have a question about fin nipping. I have longfin zebra danios in my 36 gallon in with cobra guppies, some rainbow fish, some giant danios, Corys and a blue gourami but my longfin danios are getting fin nipped... The weird thing is they are doing it to eachother. Anyone know a reason or how to prevent this? I thought this was weird but maybe not... Just looking for some insight. Thanks!

 

How many danis do you have? But yea they will chase each around and some times you get a bully. Only reason I ask is they seem to be meaner to each other if there's just a few.

 

They can also be nippy when the tank is overstocked

 

How many danis do you have? But yea they will chase each around and some times you get a bully. Only reason I ask is they seem to be meaner to each other if there's just a few.

I have 6...what is recommended?

They can also be nippy when the tank is overstocked

I have 16 fish in my 36 gal. Is that overstocked?

 

You can either add more long finned danios or the large danios, but not both. You got lots of mid dwellers. I would get rid of either the large danios and add more long fins or get rid of the long fins and get more large danios.

 

I think you probably are overstocked. What species of Rainbows do you have and how many? How many guppy's? How many cories?

 

Could also be a hierarchy issue that specimens of the same species start to nip on eachother...

 

Agree with emerald king if recently added could be trying to astablish pecking order