Acropora Granulosa bug-critter help to id

[MLDTReef]

Hello people,

Lately my yellow Acropora Granulosa is not doing very well. I has lost its color and became dark brown. I had some PO4 spikes lately and was thinking it was the problem. After some good inspection on the coral and taking some pictures of it I have found at its base two things. There is one Vermedit snail close at its base that I plan to remove asap with the next water change but I noticed at its encrusting base to white holes (highlighted with red arrows). These holes seem to coming out from the Caribsea live rock and drill through the encrusted skeleton of the coral. Can you help me on identifying these critters. The coral is in there for 4 months, it was cut well above its base and dipped prior to the introduction to the tank.

 

[vetteguy53081]

May be An acro eating nudibranch but hard to confirm as your images have room reflection, flash imprints or fuzziness

 

[MLDTReef]

Do you mean Acropora eating nudibranch? It doesn’t not move around so I think it is not a nudibranch. Like I said it looks like to having being drilled from the rock to the skeleton and out. In the left side you can see the two holes. I will try to get better images to upload.

 

[MLDTReef]

May be An ace eating nudibranch but hard to confirm as your images have room reflection, flash imprints or fuzziness

What do you mean by ace eating nudibranch? I have not found anything on such a thing. Can you please post a link? My tank is an SPS and LPS tank only. And I always cut well above the base and dip the corals prior to placement in my tank.

 

[vetteguy53081]

What do you mean by ace eating nudibranch? I have not found anything on such a thing. Can you please post a link? My tank is an SPS and LPS tank only. And I always cut well above the base and dip the corals prior to placement in my tank.

Acro-I hate spell correct

 

[MLDTReef]

Acro-I hate spell correct

Hi, I have a sixline wrasse in the system, and none of the other SPS is affected including the plating green Montipora Capricornis and 2 encrusting Montiporas (a green with red polyps and an orange with purpur polyps) or the Forest-fire Montipora Digitata. Other SPS in the tank include an Acropora Turaki, a Purple Stylophora, a Green Seriatopora Caliendrum, a Multi-color Pocillopora Damicornis, a pink Acropora Millepora and 2 encrusting Cyphastreas (purple with yellow polyps and a meteor shower).

None of the corals is a new addition and the fact that none of the other SPS is not at all affected it is making it suspicious. I placed an order for a magnifying glass to get better quality pictures and probably will have to re-post the new ones.

 

[vetteguy53081]

Hi, I have a sixline wrasse in the system, and none of the other SPS is affected including the plating green Montipora Capricornis and 2 encrusting Montiporas (a green with red polyps and an orange with purpur polyps) or the Forest-fire Montipora Digitata. Other SPS in the tank include an Acropora Turaki, a Purple Stylophora, a Green Seriatopora Caliendrum, a Multi-color Pocillopora Damicornis, a pink Acropora Millepora and 2 encrusting Cyphastreas (purple with yellow polyps and a meteor shower).

None of the corals is a new addition and the fact that none of the other SPS is not at all affected it is making it suspicious. I placed an order for a magnifying glass to get better quality pictures and probably will have to re-post the new ones.

6 lined likely won’t eat them

 

[ReeferBean]

There is such a thing as an acro eating nudibranch?

 

[MLDTReef]

There is such a thing as an acro eating nudibranch?

I have read about the Montipora eating ones but my reefing experience is small, that is the reason why I asked for help on this in the forum. I hope that it is not such a thing otherwise the rest of the acros are doomed.

 

[Staghorn]

If you think it is a hole through the coral and into the rock, do you think that the coral might’ve encrusted over some vermetid snails and what you’re seeing is the tubes? I don’t think that would be what’s hurting your coral but it would explain the holes. I would make sure you get your phosphate under control and make sure you don’t have a lot of fluctuations in parameters.

 

[MLDTReef]

If you think it is a hole through the coral and into the rock, do you think that the coral might’ve encrusted over some vermetid snails and what you’re seeing is the tubes? I don’t think that would be what’s hurting your coral but it would explain the holes. I would make sure you get your phosphate under control and make sure you don’t have a lot of fluctuations in parameters.

I will post some new pictures when I will get the magnifying glass. It is coming within next week, I do not know if Vermetid snails can do what you have said. PO4 is under control now and was the only parameter that was fluctuating lately, rest of my parameters are stable. a small frag of the Granulosa Acro is placed in another location of the tank (less flow less light) and is doing better than the one in the picture.

I think it is a combination of both PO4 spike and some critter that is not identified yet.

 

[tbrown]

Did you get an answer to this? I'm kind of thinking they look like nudibranches as well, so possibly acro eating nudis.

 

[MLDTReef]

Did you get an answer to this? I'm kind of thinking they look like nudibranches as well, so possibly acro eating nudis.

Hi unfortunately not. I took the best quality pictures I could get and examined the coral for a couple more weeks with a magnifying glass but do not have anything on them. They are not nudibranch for sure though since none of the other SPS is affected and the problem area has not grown or moved. I removed 2 vermetid snails which were close to the affected area.

The rockscape was re-arranged/moved so that the coral will have more lighting but still have no good results yet. I have to admit that the tank is not doing well since now I have a low nutrient problem, no phosphates (my PO4 values are in the range of 1-7 ppb) and started dosing some nitrates since they were zeroed. This messed up my alkalinity, Calcium and Magnesium consumption and now I am trying to stabilize it. To top it of my Hammer coral refuses to open up for 3 weeks now and I have started to see quite a lot of spots with some bubble algae. I started dosing vibrant and manually removing it were possible but no with no good results yet. I thinking of adding an emerald crab if it doesn’t go that well....