Clams and urchins?

[RobW]

I have a derasa clam about 2" or so in size. I was thinking of getting a pincushion urchin. Are the two compatible?

 

[RobW]

I wasn't sure if the urchin would try to eat it or something?

 

[Tahoe61]

Compatible, the urchin will be on the look out for algae. You can supplement using Nori.

 

[RobW]

Compatible, the urchin will be on the look out for algae. You can supplement using Nori.

Cool, thank you

 

[minus9]

I have three tuxedos with my two maximas and one noae without issues. Occasionally the urchins clean off the coralline from the shells, but nothing the clams don't shake off.

 

[jda]

I also have many pincushions in with clams and everything is good.

 

[captpetefl]

I thought so too, until the urchin crept up on my Maxima clam and ate a good-sized chunk of its mantle!
I’ve had about enough of my two urchins and their mischief - back to the fish store for you both!!!

 

[OrionN]

I do not think that the sea urchin is the guilty party here. Something is irritating the mantle. I have the same urchin and never a problem with my clams. Possible PMD.

 

[minus9]

I do not think that the sea urchin is the guilty party here. Something is irritating the mantle. I have the same urchin and never a problem with my clams. Possible PMD.

Agree! The mantle is retracted, so there’s either an irritant or PMD, but I would inspect closer and see if there’s anything on the shell or close by. Fish are another story with clam mantles, but urchins (at least the ones we keep) wouldn’t go after a mantle. Plus, from this pic, the clam’s mantle doesn’t seem to be open as it should, which could’ve been a momentary reaction while taking the pic?

 

[minus9]

Now that I'm looking at the pic with my computer instead of my phone, it looks like there's an aiptasia in the substrate that could be touching the mantle?

 

[moz71]

Now that I'm looking at the pic with my computer instead of my phone, it looks like there's an aiptasia in the substrate that could be touching the mantle?

Good catch!!!! I bet that’s what’s doing it! I have a large pincushion and a Desara clam and never had an issue. On the other hand an emerald crab ate a good chunk of clam mantle but healed nicely!