Help Identifying possible problem with my Zebra Danios

[treym563]

Hey guys,

I have a zebra danio that has been acting very aggressive towards my other 2 smaller danios, which is odd because they used to all swim around together. When I looked closer I noticed a white thing protruding from behind one of his bottom fins, perhaps where they pee/poop from? Since they are so fast and I don't have a good camera I found a picture online, circled the problem area in red, and drew in what the issue looks like in white. Any help would be appreciated I don't wanna infect my tank with anything. Thanks!

 

[Rosenweiss]

Could be wrong, but it looks like poop to me.

In any case, your aggression problems are probably the result of your numbers, not an infection. Danios are not to be aggressive in schools of less than 6 (for instance, I made the mistake of only getting two and the one was tearing the other apart).

 

[treym563]

Ok, thanks! Yeah the harassing one is about twice the size of the other two, he hasn't ripped any fins but he chases them almost constantly.

 

[Rosenweiss]

Yeah, you might see a change if you bought a few more smaller ones. Good luck!