emrald crabs - how dangerous are they?

[beerbaron]

hi all, i was thinking about adding emrald crabs to put a dent in my bubble algae population, which i heard can and cant work.

one question is, what is the chance that they will eat the algae? i plan on putting them in my sump with a piece of rock covered in bubble algae to force them to eat it, and if they dont, i wont put them in the tank.

also, for those of you who have had them, how have they acted? what species in my tank do i have to be concerned about them eating.

how difficult would they be to remove once they are in the tank? i have a rock crab in a piece of liverock which has been impossible to get out, and i am wondering if these will be the same way.

i am running out of options to control this stuff. all of my params are good.

thanks for the help
BB

 

[aliendomain]

Any crab will be a big pain to get aout of a reef although I think sally lightfoots are the worst. I'm not sure about emrald crabs eating bubble algae. I have heard of Cowries eating bubble algae but some will also go for corals. what ever you do don't try to remove it by hand inside the tank. This will cause it to spread faster, remove the rock and scrub it in a bucket filled with saltwater then rinse the rock off in a diffrent bucket.
Hope this helps and good luck.

 

[buff1]

I got two emeralds, hoping they would help with the bubble algae. So far I haven't seen them eat anything except detritus and maybe some hair algae. I've only had them about a month, however, so perhaps eventually they will discover the bubble algae. So far, they have been model citizens in the tank.

 

[kparton]

I had emerald crabs in my first tank that I set up as part of a "cleanup crew." I never had a bubble algae problem, so I can't speak to that, but I never had any problem with aggression from the emeralds. they were visible a lot and would put up their "dukes" when another crab or fish got close, but never a big problem. I don't think you'ld be able to get them out though, they are quite close to the rock most of the time and will be tough to get out.

 

[Anonymous]

I had one and he seemed harmless, but didn't eat bubble algae either.

 

[t-byrd]

they get big quick.
i had one, had to take him out. he was stressing out my jawfish,
kept going in their holes and chasing them out.

he's now in my 29g with a decorator crab and damsel,
all kicked out of the reef.

 

[sslarison]

I had alot of bubble algea at one time and the lfs reccomended an emrald crab and with in two weeks all the bubbles were gone. he is still in the tank and the only problem is he picks at polyps on occasion. Also get a big one if you can

 

[purplefirefish]

I had one in my tank. He was a model citizen. I never witnessed him eat any bubble algae, but that was only because there was none in the tank that I knew of. He went on to the great reef in the sky about 2 months ago. And I just last week noticed that in two places I have a little bubble algae growing now. My conclusion: He was containing the algae and now I have nothing in the tank to eat it. I could be wrong but I will be buying another emerald crab or two soon.

James

 

[Markymarklar]

i would try it. it couldn't hurt. if you find that you want to get rid of him all you have to do is make a fishtrap out a of a 2 liter bottle. cut the top off and invert it. put a peice a food in there overnight. in the morning you will have all kinds of things inside the bottle. this is what i did for a damsel. never worked for the damsel but it sure worked for crabs, shrimp, and snails. if you don't understand the plans for the fishtrap, just tell me and i will put a more detailed description up. i'm sure they have the plans on the site somewhere. try a search

 

[Will C1]

my emerald keeps my buble alge in check, i only can see 2 or 3 bubbles at a time so thats not to bad. he has never gone after anything other than pelets or algea and would be easy to catch as he scours the sand for pelets all the time after i feed the fish.

 

[O P Ing]

hi.
My emeral crabs behaved well until suddenly one of them decided to pull 4 of my baby maxima clams out of the shell... be forewarned.

 

[Will C1]

wow i have 2 maximas and never a problem that had to have sucked.

 

[4angel]

I took out all of my rock scrubbed the bubble algae off. then enlisted the help of an emerald crab. I think that these guys get at the small bubbles and keep this problem in check. My guy has grown pretty big but does not bother a thing.
_________________
Portuguese Forum

 

[Max Power]

be careful. If the emerald crab gets large and you have very little algae in the tank, they may get bored and go after polyps and/or fish. I had one that was about 1.5" across and it picked off my six line wrasse in the middle of the night. However, they are relentless algae eaters if there is enough to keep them happy.

 

[Anonymous]

Emerald Crabs are not to bad unless they have been exposed to Fall Out from a Nuclear Blast...then they can grow to a hundred feet wide and kill everything in there path........they even become land dwellers. We had some of these on the Planet Legton...I mean I had to leve the planet out of fear for my life! 8O

 

[Chris Witort]

I had eight emerald crabs in my 90 gal. They seem to prefer coralline algae. Never saw any eat any valonia. One that got large killed my bubble tip anemone. Use caution with these guys and be suspicious of them at all times.

 

[Anonymous]

I am...will never get one.thankyou!

 

[SCIronMike]

They get big.......... QUICKLY!

 

[beerbaron]

thanks guys for all of the input. i diddnt really get any farther though. seems like some people have had bad experiences, and others good. right now im sort of desperate. by the time they get big will they still be able to hide in crevices? i have no trust for the inverted soda bottle trick, ive tried it many times before. how big do these babys get? what types of polyps will they go after? how many of em' should i get for a heavily bubblized 75?

thanks for the help everyone
BB

 

[beerbaron]

sorry :roll: emrald i ment emerald worst spellor ever