Bad emerald crab?

[drizahy4]

Over the past week I added my yellow polyps, a few snail, a mushroom which I removed a day after I obtained it, a red hermit crab which was locked shell to shell with my blue hermit for about 3 days and has now they swapped shells with eachother.

Let me start with the yellow polyps. I got them for pretty cheap and about 3/4 of them opened fantastically in the tank. The rest looked like they were died. Possibly do to trip from the lfs? Reason being the rock was full of the polyps so when put in the bag it was rolling around on the side that the dead ones populate. Most of the time when the lights are on and he goes to hide he runs to the polyps that are open and slides in between them and will hide for a couple hours. All fine until today when I found my emerald munching on the dead polpys. This is the first time he has went after them I can see or notice. He does have enough food supply and occasionally takes care of he bubble algae that is in the tank. Other than that he munched on some algae plants.

 

[drizahy4]

Sry auto sent and can't edit a post on phone Internet. He being the emerald who hides in the open yellow polyps.

 

[Reefmack]

I'm no crab expert and only guessing that the emerald may have only been eating the dead yellow polyps. I guess you'd have to catch him in the act to confirm that he's picking at the live ones as well. I've never had a problem with my emeralds, but that's just in my case. I have heard of peppermint shrimps picking at yellow polyps, as they resemble Aiptasia.

 

[SoccerBum474]

im getting rid of my emerald crab on wednesday. it became a pain in the butt...it knocks over at least one coral everynight..

 

[drizahy4]

The culprit

Yellow Polyps Before

And after although about 50% in the front are still closed from being harassed by the crab. They did open and the rock seemed to look a lot nicer. I will try to get another picture of that tomorrow.

As you can see here the polyps in the back were damaged and dying off

The crab has tore up some of the polyps that are currently closed in the image and the water current in the tank was finishing ripping them off the rock. I turned the current away a bit off them to see how it goes. I did notice him this morning when he was eating the area that he was trying to eat the algae in between the polyps stems. Its a shame dunno what I should do with him.

 

[drizahy4]

This is him just in the rock. Every night that the lights go off he parks his but in the same spot. He has been doing this for the past week. Wasnt till this morning I saw him eat anything as all was well. While sitting there he does not bother the polyps and when the lights are on the polyps usually just open full extension with him under them.

Any other bubble algae eaters out there?

 

[Reefmack]

I had a yellow polyp rock similar to that once - it was the only rock in my tank that became covered in hair algae. I wish I'd had something at that time to eat the algae on it, but my emeralds never did. I used to pull it out and use a toothbrush to try to remove the hair algae, but would always lose some polyps doing it. I eventually gave up and lost the polyps to algae, then tossed the small rock.

Your crab may just be picking at the algae between the polyps? Emeralds often camp out in the same "home spots". I could always find one of mine sitting on top of my Pocillopora coral every evening. Have you thought about relocating that small yellow polyp rock? Maybe the crab would camp out somewhere else?

 

[Stacef]

Are you feeding your yellow polyps? They do need to be spot fed in my experience, if you are not feeding them, this could explain their dwindling population.

 

[sambrinar]

Are you feeding your yellow polyps? They do need to be spot fed in my experience, if you are not feeding them, this could explain their dwindling population.

Hmm I have these, and never spot fed them. With what?? I have an emerald in there too and he has never eaten the polyps, maybe he is just cleaning up the dying ones.

 

[Reefmack]

Same here - I never heard of spot feeding yellow polyps before. I've seen them practically take over a tank without intentionally feeding them.

 

[doubleduece]

I agree that yellow polyps dont need to be spot fed, although they will consume anything meaty, or inadvertantly drop on them i.e. pellets,etc.

Give them suckers some time and you will wish you had that crab back...

 

[drizahy4]

I have heard people saying that you can feed the polyps and they will grow like a weed(Faster than normal). In this case..

The damaged ones where on the rock when I got them. The first images show the damaged ones even with the front ones extended. They were perfect. I got both the crab and the polyps the same day. The dead ones were dying off. After I saw him ripping the dead ones off I believed he was just cleaning up and since my tank is new it wouldn't hurt to see now with a cheap rock like the yellows to see if he will attack the rest. I came home from work to see the health polyps ripped up off the rock hanging on my strands.

Well the conclusion is that last night I went to go move the rock to a lower current area in the tank so the loose polyps that still open can hopefully reattach to the rock. When I picked up the rock he was holding on for dear life. I took this opportunity to toss him of the island. He came, He cleaned, and left my bubble algae still on the rocks. I removed the bubble algae myself last night during maintenance (Cleaned it off in water change water.)

 

[DML08]

Emerald crab vs. zoa's - CVR Forums!

 

[Reefmack]

drizahy - I guess the topic was correct - Bad emerald crab! I guess I'll have to change my opinion on emeralds, and ad them to what I think of hermits - love 'em, but don't trust 'em!