Royal Gramma + Emerald crab

SneakyPete · 09/05/2012, 07:40 PM

So I put a couple of emerald crabs in my DT because I've heard they eat bubble algae. I have started to notice some in my tank, and wanted a couple of crabs anyway, so I went ahead.

Today I noticed a very odd interaction between my royal gramma and the smaller of the 2 crabs. Both were out on the live rock doing their crab thing. The smaller of the 2 was closer to the royal's cave. My royal kept going over the crab and attacking him. The crab would of course raise it's claws and the royal would quickly swim to it's hole only to come out and pick on the crab again. It broke one of the crabs claws (it has no bottom pincher on it's left claw). It also left the slightly larger crab alone.

Is my royal going to pick off my emerald crabs?

cloak · 09/05/2012, 07:51 PM

I doubt it. The mouth on that royal gramma and the hard shell of an emerald crab are two different stories. (armor) It's probably just some random aggression that will die down given time.

souperman · 09/05/2012, 07:57 PM

I swear my emerald clipped the fin off my gramma. One of the fins is cleanly sheared off, I can't think what else could have done it. The fish seems fine though with just a nub of a fin on one side. Hope it grows back...

OodleyBoodely · 09/05/2012, 09:05 PM

fin should grow back...your gramma is defending its home. Grammas are peaceful, but, they do establish a nest and will defend it from intruders. Grammas spawn in their nests so it is important for them to keep it safe should a mating opportunity arise. Move the crab to the other side of the tank.

SneakyPete · 09/05/2012, 10:00 PM

Quote:

Originally Posted by OodleyBoodely

Move the crab to the other side of the tank.

Rofl. It's only a 40B. I've seen both crabs from one end of the tank to the other.

Anyway, glad to hear this isn't unusual and also glad to hear that my gramma shouldn't kill the crabs.

I'm really happy I added the crabs. They are very cool to watch and now when I come home from work I get to play a game of find the crabs in the rockwork, which for a color blind person, is quite difficult

09/05/2012, 07:40 PM	#1
SneakyPete I see you Join Date: Jul 2011 Location: Northwestern Minnesota Posts: 513	Royal Gramma + Emerald crab So I put a couple of emerald crabs in my DT because I've heard they eat bubble algae. I have started to notice some in my tank, and wanted a couple of crabs anyway, so I went ahead. Today I noticed a very odd interaction between my royal gramma and the smaller of the 2 crabs. Both were out on the live rock doing their crab thing. The smaller of the 2 was closer to the royal's cave. My royal kept going over the crab and attacking him. The crab would of course raise it's claws and the royal would quickly swim to it's hole only to come out and pick on the crab again. It broke one of the crabs claws (it has no bottom pincher on it's left claw). It also left the slightly larger crab alone. Is my royal going to pick off my emerald crabs? __________________ 40B in recovery mode Trumpet coral, Kenya tree, unknown Zoa Skunk Cleaner, 2 Ocellaris Clowns, Royal Gramma Current Tank Info: 40B w 29 sump. 50 lbs rock

09/05/2012, 07:57 PM	#3
souperman Registered Member Join Date: Dec 2010 Posts: 262	I swear my emerald clipped the fin off my gramma. One of the fins is cleanly sheared off, I can't think what else could have done it. The fish seems fine though with just a nub of a fin on one side. Hope it grows back... __________________ No.

09/05/2012, 09:05 PM	#4
OodleyBoodely Registered Member Join Date: Jun 2001 Location: Azle, Tx Posts: 754	fin should grow back...your gramma is defending its home. Grammas are peaceful, but, they do establish a nest and will defend it from intruders. Grammas spawn in their nests so it is important for them to keep it safe should a mating opportunity arise. Move the crab to the other side of the tank. __________________ 37gal w/LED lighting with cement/oystershell/perlite background, DSB, 20l sump with 30lbs lr, biopellets in reactor, Reef Octo skimmer, 1 pajama cardinal No corals at this time. -

09/05/2012, 07:51 PM	#2
cloak Moved On Join Date: Jul 2000 Location: Stockton, CA Posts: 14,854	I doubt it. The mouth on that royal gramma and the hard shell of an emerald crab are two different stories. (armor) It's probably just some random aggression that will die down given time.