Hippo Tang - Strange Spot, see Pic (not ich)

[chana]

Has anyone seen anything like this?
Blue hippo (small, about 2.5") has strange white circle on side.
Doesn't look like ich. Center is normal blue color, or maybe a wound of some sort, but blue. From there, it fades white in a PERFECT circle, total about 1/4" diameter. Looks like a small washer. Area is not raised, or showing any other sign of trauma or disease. Fish is fine...eating, active.
This wasn't there last night.
Tested water just last night, all perfect, except calcium low.
Currently feeding alternately: Formula One, Cyclopeeze, Emerald Entree, Brine Shrimp, Silversides, Phytoplankton, Zooplankton.
Tank is well established. Fish is fairly new, but quarantined before tank entry.
Other livestock: Maroon Clown, Flame Angel, Blenny, Coral Banded Shrimp, and Black Urchin (maybe he got stuck by the urchin?) & various snails/crabs.
Corals: Pagoda Cup, CandyCane, Bubble, Devil's Hand, Toadstool, Cabbage, Tube Anemone, LT Anemone, Carnation, various zoo's, various mushrooms, Xenia, Feather Duster

 

[sepulatian]

Welcome to the boards!!! It is possible that he swam into the urchin. Stress marks and diseases do not have that perfectly circular formation.

 

[chana]

Thanks!
It's possible, something we thought about. Guess we will have to do research to find out what that would do to the fish.

 

[sepulatian]

Originally Posted by chana
http:///forum/post/2504814
Thanks!
It's possible, something we thought about. Guess we will have to do research to find out what that would do to the fish.
What kind of urchin do you have? Long spined urchins do have venom in them. If the fish simply got a prick then he will be fine.

 

[chana]

Not sure what kind it is... here is a pic
Have you ever seen what a "stick" from an urchin does to a fish?

 

[sepulatian]

That is a long-spined urchin. The spines are equipped with a painful irritant. This is their defense against predators. It is not life threatening, but probably hurts like heck. Watch this fish very carefully. He may get a bacterial infection from this. People are supposed to treat it with an antiseptic. The fish may need antibiotic treatment if it gets red. You need a fully cycled quarantine tank for that. If you do not have one then set one up now. It has to be cycled.

 

[chana]

Thanks!
If anyone else out there has any knowledge, or can confirm if this is from the urchin, your input would be appreciated.

 

[chana]

Tang is fine,
I think it was the urchin
The next day there was no white spot, but there was a black pin hole in the center. It has all cleared up.