Help! Something weird on my fish

[ONeill074]

Today I noticed that each of my 3 Zebra Danio's have a white bump on their tail fin. I looked up fish diseases, but none of them seem to describe what I see. Ich is described as multiple small white spots the size of a grain of salt. They each only have one bump that is a bit larger than a grain of salt. It doesn't match any of the fungus descriptions either. It doesn't look "cottony" as they describe.
Does anyone know what this is? Is it something I should be worried about?

 

[TLM4x4]

Sounds like Ich to me heres a link for you...

http://www.cichlid-forum.com/articles/ich.php

 

[FroggyFox]

well if there's only one and they dont multiply and start looking like someone sprinkled salt on your fish, then its probably not ick. Sometimes when fish bite at each other or get injured the area around the wound turns white...so you should make sure thats not the cause.

Keep a close eye on if they're eating and their behavior...and do some extra water changes just to be safe. Many fish sicknesses can be tied to poor water quality.