How Bad Are Gorilla Crabs - Should I Get Them Out?

[650-IS350]

Are you sure its a Mantis , Since TBS comes with a LOT of pistols too... I got about 7 or so pistols that came with the rocks.... sometimes it sounds like war in my tank... I seen the pistols so I konw its them... and have never lost any snails too..

 

[wickedfood]

If it makes you feel any better, the mantis that hitched on my rock didn't do any harm to my hermits, snails or fish. He just went after clams and barnacles. He eventually became comfortable enough to come out from the rock during evening feedings of frozen krill. One night I just netted him--first attempt--shockingly easy! The LFS was happy to take him, and gave me a $10 credit. And, I think he might have disposed of most of the small crabs, so my overall mantis experience was actually a good one. Go figure...

 

[hunter99991]

crabs

crabs

Do all gorilla or bad crabs have black tips? I have some hairy crabs but they don't have black tips.

Brent

 

[Macroculture]

The 'Gorilla' crabs do have black tips, but there are lots of other mud crabs that don't. All of them are predatory or predatory scavengers and attack snails, other crabs, shrimp, hard and soft coral, hermit crabs, clams and other sessile inverts. I dislike these crabs with a passion reserved for heavy infestations of Aiptasia and bristleworms. At least they are difficult to breed due to their planktonic life cycle. I don't usually like to kill anything in a tank, but I make an exception for these crabs. But if you have larger fish and no other inverts these make excellent scavengers. If I can catch them alive I let them go in the sump (not refugium), if I can't get them alive I use a wooden stick or ice pick to kill them in their hole. These crabs are the reason I started keeping an octopus to cure live rock and eat these crabs prior to placing live rock in the tank. I hate to lose the pistol shrimp and other good hitchhikers, but it is worth it not to have to fight the crab fight in a tank full of coral.

 

[Macroculture]

I should add though that the live rock from Tampa Bay Saltwater is some of the best I have ever seen, and had more coral and macroalgal growth than a lot of live rock that had been in tanks for months.

 

[Brent Thomann]

I thought those black tipped crabs are called stone crabs?

I dosed mine with Alk., haven't him since.

 

[bobt2]

there are hairy crabs that are red mithrax. good crabs! check the tbs site. i left mine alone

 

[Macroculture]

True Stone Crabs are Menippe mercenaria , and are a type of Mud Crab that grows very large, up to four inches across. They usually have black tips on their claws, but many other Mud Crabs do also. If you look at the tip of the claws, Mithrax crabs have flat tips like two razor blades put together or flat wire cutters, Mud Crabs (Gorilla and Stone included) usually have pointed claw tips like two fingertips touching.

 

[Grand Wazoo]

<a href=showthread.php?s=&postid=8320155#post8320155 target=_blank>Originally posted</a> by ckumlien
take a container like a canning jar, fill it with reef rubble to create a maze. At the bottom of the container put some flake food in there. You will have the crab trapped.

not sure how much damage they cause. I heard lots of rumors and that was enough to make me remove mine.

Ive found that these little bastards are too smart for traps--Ive caught mine using those spring loaded claws and sneaking up on them. They are smart and quick. Tough catch.
The harm theyve done to me are to my blue hermits--the little bastards have bumped off a few. No other damage...

 

[hunter99991]

Well I caught the big crab and gave him to a friend. I still have several small ones I think. I hear lots of ticking coming from the aquarium but haven't been able to find where it is coming from.

I saw the big crab with a shell in its mouth and decided it had to go.

Brent

 

[650-IS350]

Only GOOD crabs are Porcelin ( which you get from TBS rocks ) and Acro crabs ( which protect your acroporas )

 

[Tobman]

I've caught many crabs now using the following methods:

- pulling out a piece of rock that they are crawling under - this is how I caught the big ones

- grabbing them with hemostats, caught a couple this way

- baiting a mantis trap with fish, caught a few this way, but not the mantis :-(

 

[650-IS350]

In case of TBS which is quite big and heavy baiting and spearing are the few alternatives... besides renting a OCTOPUS to clear the tank of mantis and crabs..