Crabs in a reef tank

[Haleyf1024]

Hey guys! So my tank has been set up for maybe 4 months now, and I am starting to see all the larger hitch hiker that came with my florida live rock. About 2 weeks ago I found a 1" Ruby Crab (same as an Emerald, but bright red) and he was doing great. He and my larger Emerald (3") get along and seem to both be thriving in my reef set up. Today, I was feeding and looked into my Emerald's crevace and saw another crab that apparently has been living with the emerald. It has the fans, so I guess it is a porcelain. He is redish pink in color, not the typical blue or white w/brown. I have read a few posts about them damaging anemones or corals, but my RBTA, coral, and clam are as happy as ever. So, will I need to watch this crab (who has already moved out of site) or should he be okay in the reef? Once the Ruby grows up, will any of the three fight?

 

[Calappidae]

Porcelains are harmless but I would keep an eye on it solely because you don't know for sure that it's a porcelain.

 

[adamyaws]

I've been Emerald hunting and trapping lately. At first they were fine and fun to watch. Then they started taking swipes at fish and other things. They are NOT underfed but they are curious and constantly a bit devious.

They're also smarter than you think (or should I say clever-er.) One has been particularly difficult to catch since he's learned that whiskey glasses with food in them are TRAPS.

 

[Haleyf1024]

My emerald is "special"... He kind of just sits around all day rubbing his claws and legs against each other... He cleans nicely though and gets along with my RBTA except stealing food once in a while. I give him a salad shrimp once in a while to make sure he doesn't get too hungry that he messes with the nem or zoas. If he isn't a porcelain crab, what other crabs have those same feather/comb things?

 

[Betta132]

Porcelains are the only crabs that have the feeler things. There are also anemone crabs, but that's a kind of porcelain that often lives in anemones.