Do all urchins dislodge rock work..Or is it just Pencil Urchin?

[miserkris]

Do all urchins dislodge rock work? Or is it just Pencil Urchin?

I have some LR that is not secured and am worried!

Now I have a tuxedo and a rock urchin (both same size ~ 2.5" incl spines).

Pls advice!

 

[Nina51]

all urchins are capable. some just do it more than others. i have 2 pincushion urchins that can and will dislodge some pretty big frags.

 

[Calappidae]

It depends how tight and secure your rocks are. Mine never causes problems, but I can sometimes see a rock elevated when my rock boring urchin is near it.

 

[Nina51]

my tuxedo urchin, all dressed up and nowhere to go.
<a href="http://s6.photobucket.com/user/Ninapearl/media/TANK/frag_zpsfc99d2a5.jpg.html" target="_blank"><img src="http://i6.photobucket.com/albums/y203/Ninapearl/TANK/frag_zpsfc99d2a5.jpg" border="0" alt=" photo frag_zpsfc99d2a5.jpg"/></a>

pincushion urchin, rearranging the furniture.
<a href="http://s6.photobucket.com/user/Ninapearl/media/TANK/10291857_796438777043354_232983905534652853_n_zps888f510a.jpg.html" target="_blank"><img src="http://i6.photobucket.com/albums/y203/Ninapearl/TANK/10291857_796438777043354_232983905534652853_n_zps888f510a.jpg" border="0" alt=" photo 10291857_796438777043354_232983905534652853_n_zps888f510a.jpg"/></a>

 

[Sk8r]

the tuxedo and pincushions are the least disruptive I've found. The long-spines and pencils more so.

 

[miserkris]

the tuxedo and pincushions are the least disruptive I've found. The long-spines and pencils more so.

Good point.

So when coralline runs out ....then will they eat ha out of desperation?

Will sub species of urchin attack each other?

 

[Betta132]

Tuxedos will happily eat hair algae, though they do tend to pick it up and haul tufts of it around.
Urchins basically ignore each other. They don't have brains, and they don't really do anything other than eat and (in the case of pincushions and tuxedos) carry things.

 

[Calappidae]

They will irritate each other occasionally. Urchins need grazing room, and thus having more than one will cause a food shortage for the other, and when in contact, a poke war to try and sting the most puncture wounds for infection. Other species like tuxedo, pencil, and pincushion get along fine as they can't sting, but they will try and ram into each... which just take 10 second to picture that in your head and you'll soon realize how harmless they are.. I've also witnessed tuxedos "arresting" others by carrying them around until they run out of food.

That's some tuxedo gentlemen's dispute right there.