Evidence that gorrilla crabs are bad?

[OldmillXxX]

I am curious if anyone has photographic proof that gorilla crabs do harm to an aquarium. I do understand the concern, but I read thread after thread of gorillas always catching a bad rap the moment they are discovered. It seems to always be suggested that it be "removed immediately!". Why?

I by no means have a prize tank and my most expensive fish was maybe $30. I did purchase a rock that was not only covered with hairy mushrooms, but also was full of various crabs, some of which fall into the gorilla category. I initially removed five and banned them to the sump as I was told. Since then, a few have popped up out of nowhere and are still in the main tank. One for sure of the gorilla type and one or two others that have the claws of a mithrax.

As stated, I am curious if anybody has photographic proof that the crab is causing harm, or is it just the thing to do these days?

Thanks and I look forward to a good discussion.:rollface:

 

[OldmillXxX]

Anyone?

 

[willtel76]

I don't have pics of it but I have seen one snacking on a gorgonian like it was a corn dog. That was enough proof for me.

 

[Fountainhead]

I've posted these elsewhere so I apologize to those who've seen these before but this:

did this:

Any questions?

 

[LobsterOfJustice]

Mine ate a bunch of snails and a nudibranch.

 

[OldmillXxX]

Now that is some evidence! How did the star recover there Fountainhead? How big was the crab compared to the star?

More?

 

[SDguy]

That's a gorilla crab?? Did I miss a class? I thought when people say gorilla crab, they mean the ones with black carapace/claws, and furry off white legs, no?

 

[BTTRFLYGRL]

Whatever type of crab it is...it looks very evil:eek2: :eek1:

 

[Fountainhead]

<a href=showthread.php?s=&postid=8178835#post8178835 target=_blank>Originally posted</a> by OldmillXxX
Now that is some evidence! How did the star recover there Fountainhead? How big was the crab compared to the star?

It hid out in the rocks for a couple of weeks and emerged like this:

Made a full recovery. The star's disk is about the size of a quarter, and the crab (including legs) was about the size of a silver dollar or maybe a little larger, so he was pretty big. They both seemed to like the same rock and tangled more than once before I finally got the crab out. He was seriously mean.

 

[hahnmeister]

Well, that isnt exactly what most consider a gorilla crab, but its close enough. You have to look a the claws... most crabs with narrow & sharp pincers are designed for ripping apart flesh with them. Crabs with flat plates in their claws (like emeralds), are designed for algae/plant picking.

 

[OldmillXxX]

Like I said, I have a mix with both kinds of claws and no problems to date. I see the flat plates grazing on algae and the sharps eating the food when I feed. Most are pretty small; I want to see what happens.

Are those eggs Fountainhead? The first big girl I saw in the mushroom rock came out one night and fanned the clutch of eggs at me as if to say "look what I got for you and your tank!"

 

[LadyReefNeck]

I discovered this guy/gal in a large piece of rock I'd gotten from a fellow reefer. It was the size of the palm of my hand. I was never able to get a confirmed opinion if it was a gorilla or a mithrax.

I saw it emerge from the rock one night about 2 hours after lights out and was checking out the mandarin goby sleeping just below on the rock. The next day my mandarin was missing. That afternoon I find 1/2 my mandarin sucked up against the bottom of the powerhead and can see the other 1/2 inside this big rock (through the hole the crab had come out of).

Needless to say the rock came out of my tank. I then spent 4 hours spraying the rock with a hose (Fresh water), poking into the rock with a wooden spoon and various other items trying to get the crab out. Finally I just took a hammer and chisel to the rock and tapped out a fist size whole where I thought he was located. The piece of rock fell away and the crab with it.

It got banished to a large tank at a LFS with an eel as I was not about to let it make a meal out of any of my other fish.

 

[Fountainhead]

<a href=showthread.php?s=&postid=8179477#post8179477 target=_blank>Originally posted</a> by hahnmeister
Well, that isnt exactly what most consider a gorilla crab, but its close enough.

This crab (along with his "posse") arrived in a load of TBS rock. It's extremely common to TBS rock and in the TBS forum it's referred to as a gorilla crab. But maybe it's technically not, I dunno.

The only thing that matters to me is that he's out. Shortly after I snapped his portrait I smashed him up into pieces and tossed him back in the tank. The other serpent stars devoured him within seconds, in an apparent show of solidarity for their injured brother. It was enough to reduce a grown man to tears. Well, almost. Sort of. Not really I guess. But it was still cool.

 

[sknich]

now thats justice. attempt to kill and be killed, only to sustain the thing that you were attempting to kill

almost poetic

 

[hahnmeister]

LadyReefNeck,
Its hard to tell from the back, but it looks more like a stone/box crab from the back.

 

[OldmillXxX]

The one in my tank that flashed her eggs to me looked like the one that LadyReefNeck banned.

Anyone else have proof that the black clawed crabs are indeed evil?

 

[aclos3]

Fountainhead, that is awesome justice! Although the thing was brutally killed by you, it served as food for starfishes... so that makes it ok, almost natural even

 

[hahnmeister]

FWIW, all crabs with claws are bad. Many have had emeralds attack/eat other critters if the opportunity presents itself. Hermit crabs will rip snails out of their shells for a snack, or just to see if the shell is nice. Porcelain crabs have claws that are weak, and pretty much for show, and thats what makes them the exception to the idea, along with sand-sifting crabs. But every other crab I can think of is only as trusted with other things that are too big to fit in its claws... otherwise its a potential target.

 

[OldmillXxX]

C'mon fellow reefers! Is that it? One picture and we all ban the beast to the sump or back in the tank as "food"?

For every thread that includes a "better get it out of there as soon as possible", or "BAN IT TO THE SUMP!!!" there must be a few more pics out there that show what these little monsters are "preprogrammed" to do.

Bring on the pics!

 

[hahnmeister]

Hey, I banned all crabs from all but one of my tanks. As far as Im concerned, snails do just as good a job, if not better than, of removing algae and cleaning compared to crabs. If you really want to see some cool battle pics, check out the 'Tim the Supermantis' thread in the mantis forum. There are plenty of guest starring crabs there.