Emerald Crab - How Many?

[Tom39]

So I was thinking of adding 2 more emerald crab to my dt and was wondering how many would be too many.
I currently have a 50 gal with about 75# of LR and only one emerald crab at the moment. I was placing an online order and the deal on the crabs is a BOGO deal. I am not sure if 3 crabs would be overcrowded in my 50g. What do you think?
If 3 would be too many, has anyone ever added one to their refugium? I only have a small refugium with a bit of LR, LS and cheato. Do you think the 3rd would be happy there?

Thanks
Tom G

 

[Calappidae]

Didn't take long for my 2 emeralds to begin chasing my scooter blenny after adding them. Although thats my experience.. I think it's personal preference on how many as long as there is enough algae and they are all fed well. An emerald would be fine in a fuge, it may also help clean up any scaps that might end up in there.

 

[ATLL765]

Crab in the fuge is kinda contradictory to the purpose of the fuge. The crab would surely be fine though.

 

[Cancros Amo]

When this question comes up (How many emerald crabs is too many?), what criteria are we looking for?

For example, I have a tiny 2.6 gal saltwater aquarium with one emerald crab, two red legged hermits. That's all. I love crabs!

So, other than fighting over food, or predation on fish and plants, what would one be looking for in sizing up a tank for crabs?

I'm brand new to the hobby, and really appreciate anything I can learn. Thanks!

 

[Calappidae]

2.6 gallon will be extremely difficult to maintain with salinity and ph changing every day.

IMO anything under 10 gallons shouldn't be a saltwater setup because of how hard it is to maintain.


There really isn't an offical minimum tank size on inverts but depending on their tankmates for territory you might want to go alot bigger. Also depends on their food supply and compatibility.

 

[jayjerk]

these things are pest imo. always chasing down my more peaceful fish.

 

[Trock577]

I have had a couple of fish disappear after adding emeralds

 

[Calappidae]

If emeralds have enough algae and space then they'll ignore your fish completely. I had a ten gallon with GHA, and added three emeralds.. once they ate it all I noticed them chasing the sexy shrimp so I quickly moved them to the 125 where there is plenty of algae for them and they show no interest in the fish.

 

[62SVT]

So 1 Emerald crab in a 100 gallon aquarium would probably be happy and peaceful as opposed to several.

 

[Reeferz412]

I have one in my 46. Good enough to eat up some scattered bubble algae from some frags I picked up. It also eats hair algae and any sort of food I throw in the tank. One should suffice.

 

[Jpugh73]

I caught mine eating my gsp at night when the polyps weren't out snagged him up and into rdsb

 

[BlueFyre]

I have 4 in a 65. They have never bothered anything.

 

[rssjsb]

I caught mine eating my gsp at night when the polyps weren't out snagged him up and into rdsb

Some would consider that a public service.

 

[fifthtoe]

I have one about the size of fingernail that killed my royal gramma. Had the RG in quarantine for about 4 weeks and he only lasted 5 minutes in the display before he was killed.

 

[justthewife]

one is too many

 

[Calappidae]

If your tank is big enough and has plenty of algae to feast off of then chances are it'll show no interest in your fish.