Possible SPS predator - Any Ideas?

[Cam]

Hi,

I have been having problems with my SPS for a long time now. No polyp extension, receeding tissue and strange stunted growth. Today after having a bit of a move round of my huge clam I decided to remove the few bits of SPS I had that were not doing good. On closed examination I noticed these small round hard-ish 'cases' on the corals near the edge of the tissue recession and other parts of the dead skeleton. I have a suspicion that they could be simple egg cases of some snail or critter but I am a little concerned that they could be something more sinister and have something to do with my SPS problems.

Any thoughts on the id of the items would be appreciated. They are about 1mm long as you can see from the small kitchen knife that they are on to give scale.

Thanks in advance,

Cam.

 

[ingtar_shinowa]

wow nice camera, i want to follow along!

 

[96gts]

Looks like Stomatella Snails. They are herbivorous grazers that eat microalgae.

http://bb.wetwebmedia.com/viewtopic.php?f=25&t=181

 

[Cam]

Thanks for that but they are not stomatella, unless stomatella lay these as egg cases. I've got hundreds of stomatella in the tank but these are not the same.

Cheers,

Cam.

 

[Znut Reefer]

They do look like egg sac from stromatella snails. Do you have these snails in your tank? If so they will lay eggs just about anywhere including the bases of acros.

 

[Cam]

Thanks, I tend to agree, my tank is stomatella city! I hought they were just broadcast spawners though?

Cam.

 

[Baros]

They look more like the egg casings of a Columbella (Dove snail).

 

[Cam]

Figures, I have loads of those too. At least it rules out any sort of acro predator.

Thanks,

Cam.