Chroims tail and Sea Urchin Info?

[SHARPiE]

Hi All,
Two part post here. Not sure if this is the right section - but a mod might be able to move this to the right section.

1 - I got home today and my chromis was missing half his tail? Looked like its been chewed. He's acting normally, and swimming fine, but I'm at a loss as to how it happened! Tank mates are in my signature - and no-one's been acting agressive toward each other. Caught in the rocks maybe? I can't get a pic, but it doesnt look like fin rot or anything nasty.

2 - My sea urchin is excreting this cream powdery substance from the top, inbetween some spines. I'm thinking this is poop, but from my research, the poop is usually in pellet form. It trickles down the side of the urchin, inbetween the spines. I can tell he's eating well as he's made a dent in my coraline algae (plenty more where that came from). **edit** I looked at the anatomy of an urchin and the powder seems to be coming from it's "bottom".
Pic link below:

 

[austinsdad]

Any new rocks or coral added lately where a predator might be a hiding? Bad crab or mantis???

 

[StripesTheEel]

1 - Overzealous cleaner wrasse possibly or aggressive dottyback

2 - Looks like sand, pic abit blurry though.

 

[SHARPiE]

Any new rocks or coral added lately where a predator might be a hiding? Bad crab or mantis???

I started another thread a week or so about the possibility of having a manits. This might be the case. No new rock - and only the corals that came as hitch hikers on my original LR, but i've heard the clicking more frequently of late. I'll look harder for him with red light. Thanks Ray.

1 - Overzealous cleaner wrasse possibly or aggressive dottyback

2 - Looks like sand, pic abit blurry though.

Thank Matt - It does look like sand coming out - but I have crushed coral as a substrate. It comes out in a slow fountain resemblance. A little more info on behaviour: The chromis has a little hiding spot in some LR crevices - and wards away the dottyback and wrasse. Haven't seen any agression from the wrasse or dotty, I'll watch how they interact a little more closely.

 

[austinsdad]

Hearing clicking when you don't know of anything you've put in the tank that clicks... sounds like a very good possibility for a culprit.

 

[SHARPiE]

Just inspected the tank with a red light - can't see anything yet. I'll be on a stakeout for a while.

And an update on the urchin - all the sandy stuff has gone - I suspect I saw him going to the toilet.

 

[Jimbo7]

My dottyback was a huge bully. Almost killed several fish. But if you haven't seen anything, chances are you are alright on that front.

Mantis or other predator seems likely for the missing tail.

Start soaking your food in Selcon or other garlic immunity booster to help him heal and regrow.