Who is eating my SPS?!

[Wrasse-cal]

I suspect my yellow tang or bicolor blenny started to nibble on my acropora. Nibbling might be an understatement. The tips are actually being bitten off. There are also some marks elsewhere that look like big bite marks. :( This really sucks. 6+ months and they've been model inhabitants. The odd part as well is the Tang and Blenny are well fed and fat. They have a clip of ulva in the tank and are fed TDO and LRS daily.

I did a dip in Coral Rx and saw nothing i.e., no AEFW/red bugs. Plus, I suspect I'd see skeleton, with flatworms or bugs. In my case, I have literal chunks missing.

Is this fish damage or something else? Do I have to re-home my fish?

 

[Amps Reef Life]

I would wait to catch the fish in the act to make sure you remove the correct one but I have heard from locals and one I knew well that their tang went rogue and started eating corals. NO fish is truly safe and they are all different. This look like nibbling for sure. My fox face did it and I had to remove him. The damage my fox face caused started out looking just like your pictures before he stressed out a few colonies and killed them off. I have also introduced hermit crabs and caught two eating on my sps but the damage they do is much different than in your pictures but just another thing to keep an eye out for. You never know what's in all those shells.

 

[Wrasse-cal]

I would wait to catch the fish in the act to make sure you remove the correct one but I have heard from locals and one I knew well that their tang went rogue and started eating corals. NO fish is truly safe and they are all different. This look like nibbling for sure. My fox face did it and I had to remove him. The damage my fox face caused started out looking just like your pictures before he stressed out a few colonies and killed them off. I have also introduced hermit crabs and caught two eating on my sps but the damage they do is much different than in your pictures but just another thing to keep an eye out for. You never know what's in all those shells.

Thanks. I haven't been able to catch either fish in the act, which is troubling.

 

[Amps Reef Life]

Thanks. I haven't been able to catch either fish in the act, which is troubling.

I totally understand. Staying up past my normal bedtime night watching the tank is what did it for me. I couldn't find out which fish was doing. I had to be still and just wait.

 

[GoldeneyeRet]

Ecsenius blennies are notorious sps nippers, I'd wager it's the bicolor

 

[Wrasse-cal]

Ecsenius blennies are notorious sps nippers, I'd wager it's the bicolor

Would the blenny be able to actually remove chunks of skeleton?

 

[FoxyFace]

Do you have large snails? Sometimes they fall and break things.

 

[Wrasse-cal]

Do you have large snails? Sometimes they fall and break things.

All of the frags are on a frag rack. Nothing likely could have fallen on them.

 

[Livinlocal]

Are those the only fish you have in there?

 

[BestMomEver]

I’ve had a Rabbitfish nibble lps but I’ve never heard of a yellow tang eating SPS. I also wouldn’t think the Blenny could cause that much damage but anything is possible.. good luck finding the culprit!

 

[Wrasse-cal]

Are those the only fish you have in there?

Clownfish, chromis and anthias are the only others.

 

[Livinlocal]

Yeah, then I would lean towards the yellow tank. I had one years ago that would nip my sps but not to that extent. The reason I asked what other fish, because I have had multiple blue tang’s bite huge chunks out just like your photos. How big is your yellow tang?

 

[Wrasse-cal]

Yeah, then I would lean towards the yellow tank. I had one years ago that would nip my sps but not to that extent. The reason I asked what other fish, because I have had multiple blue tang’s bite huge chunks out just like your photos. How big is your yellow tang?

About 4-4.5 inches

 

[29bonsaireef]

Have any emerald crabs?

 

[Wrasse-cal]

Have any emerald crabs?

Yes.

 

[29bonsaireef]

Probably them. I always have this issue with emerald crabs. Caught them in the act countless times

 

[DesertReefT4r]

I had a bicolor blenny take a liking to sps but is did not nip off tips. Emerald crabs will and can for sure break off pieces of coral and eat them. Ask me how I know but I get you can guess.

 

[Wrasse-cal]

Can anyone recommend a crab trap?

 

[29bonsaireef]

They can be real tricky to catch. If you can make a little noose to get around their claw or leg, that will hold them in place. Then I usually get some long tong/tweezers. Grab them around their carapace, because the claws will come off easily, they have a very strong grip. Other techniques are not as pretty. You could try a little trap of some sort but I haven't had success with that.

 

[Charlie’s Frags]

Can anyone recommend a crab trap?

I read something years ago a about putting a large chunk of shrimp in a shot glass next to a rock so the crab climb up the rock and can fall in the glass but they won’t be able to climb out. I never tried this though.