Hermits Eating Acans!? / Sick Corals

[iammitch3479]

Woke up this morning to see my hermit crabs all over both of my acans. Now I looked this up and everything I read said this is highly unlikely unless they were dying. But I just saw them both inflated up nice and big yesterday but now they look pissed and one of them looks kinda white. And now I noticed my toadstool looks white in a spot also. Tested of course and nothing was out of the ordinary, there are no fish in it right now (they are in qt)

Here are some pictures of yesterday/earlier this week and today.


http://imgur.com/a/fsNSF

 

[stingythingy45]

Can't see the picture.
Is there anyway to catch the crabs and put them in a sump?
I don't have any crabs in my tank. Mostly cause they will kill snails for the shell.

 

[iammitch3479]

Its all the crabs, it's not a single crab. I find different ones on them all the time literally picking at the flesh.

 

[wpeterson]

We had dwarf zebra hermits, red legs, blue legs and scarlets in our original mixed reef tank.

I caught all but the scarlets eating corals, especially Acans eventually. The acans would be fine for a month or two, but then the crabs would get hungry or a taste for them and their tissue would get eaten quickly.

I've found new homes for all of our hermits but the remaining two scarlets and replaced them with Nassarius snails. The Nassarius can be even more efficient at eating anything meaty (but are actually reef safe - they leave LPS corals alone) and do a better job of getting into the substrate.

Based on my experience, I would not consider most/any hermits to be reef safe in the long run. They won't bother your SPS, but any fleshy LPS like Acans are destined to become a midnight snack.

My experience is all with nano reefs (a 29gal and 22gal). It may be that in a larger 60+ gal system the hermits have more territory to forage in and are less likely to eat your LPS.

The other misbehaving critter we've battled were overly aggressive/hungry peppermint shrimp, who also had a taste for Acans and soft coral tissue. We found homes for the worst offenders there but still have two for aiptasia control.

 

[delta]

put something around the coral and watch it closely. A section of a two liter bottle sunk into the sand about 2-3" high around the acan will do enough to keep them at bay. The coral looks to be receding. But this will give you time to see if it will come back and if the hermits were just eating a dying coral or not

 

[saltwaterB]

Hermit Crabs are scavengers....so they are there to clean up the mess....I have never had them eat anything that was healthy....as long as they are well fed. Any scavenger that does not find enough food will obviously become a predator...and then they can eat anything they want...

So I would have to say that the Acans were going down hard and the Hermits smelt it and just did their job.

 

[nemodan]

Hermit Crabs are scavengers....so they are there to clean up the mess....I have never had them eat anything that was healthy....as long as they are well fed. Any scavenger that does not find enough food will obviously become a predator...and then they can eat anything they want...

So I would have to say that the Acans were going down hard and the Hermits smelt it and just did their job.

+2 to this comment. My 2 tanks are full of red and blue legs hermit crabs. One tank has many Acans and I never had a problem. I feed once a day and very well thinking that there are more than fish in the tank. There is a big Cleaning Crew working and they need to find food too.

The Acans of the first picture are not well expanded. But I had mine in that way from time to time. But they always finish expanding a lot, like balloons.

 

[frank180reef]

Hermit Crabs are scavengers....so they are there to clean up the mess....I have never had them eat anything that was healthy....as long as they are well fed. Any scavenger that does not find enough food will obviously become a predator...and then they can eat anything they want...

So I would have to say that the Acans were going down hard and the Hermits smelt it and just did their job.

Yup agree, your alk is likely low