Amphipod eating my acro?

[JaneG]

Hi all,

There is one acro I got as a $10 frag that was all browned out. I've had it for about 2-3 weeks and it has actually started to color up to green quite noticeably so I think it's doing well in my tank. However, the polyps, starting at the base, have been disappearing slowly. I have no idea what's causing this as my calcium, alkalinity, and magnesium are all in check as are my nitrates, phosphates, salinity, water source, etc.. There is definitely healthy tissue, but the polyps are just slowly disappearing from the bottom up.

There are a lot of amphipods in this tank...and I don't have any fish that would eat them readily (I only have 1 jawfish). There is one amphipod in particular that I keep seeing - it's quite large and on one side it looks like it broke 3 or so of its legs. I see its molts quite often. As soon as the lights go out, I can see it just staying on this acro and I don't know for sure but I think it might be eating it! Is this unheard of? I searched and didn't find much. What else could cause the polyps to disappear with healthy tissue? I did a Revive dip and there wasn't anything on it. My radioactive dragon eye zoas have also had closed polyps for a long while now (even though I've dipped them and nothing coming off). Maybe a wrasse of some sort would help? Thank you!

 

[JaneG]

I normally hate to bump topics, but the polyps are still disappearing. Any ideas?

 

[reefsafe]

is it possible it's a flatworm?

 

[WayOfTheReef]

Amphipods don't harm corals as far as I know. They will eat dead tissue, so your polyps might be decaying and the pods are eating it. Something else is causing your problem. good luck

 

[Reefnub]

^--- yup, it happened to me too except it was on a birdsnest and dying zoas. I was confused too and I kept searching on google. Apparently others experience this too, I just turned up the flow on my vortechs and then the amphipods stopped bothering my corals. When a corals dies/decays a little, the amphipods will attack it before it gets to healed so some people think amphipods killed their corals.

 

[JaneG]

Thanks everyone! I am super confused. The skin is coloring up nicely...it started out completely brown and now it's turning to a nice deep green/blue color. However, the polyps are still disappearing. I think light and flow are fine...the tank is 17.4g in the display (20g sump) with an MP10 on 90% and the lighting is LEDs. My Alk is 8dKH, my Calcium is at 440ppm and my Magnesium is at 1300ppm- I've been testing Alk and Calcium daily for the past two weeks and there have been no fluctuations. I had a nitrate problem (~10ppm) a little while ago (about a week ago) that I have under control now. For whatever reason, my LFS was selling RO only water and didn't tell me- it was not RO/DI. I have it fixed now, however, and my nitrates are now under control... maybe that caused it? I don't think it's a flatworm...I've basted all my coral and nothing's coming off and nothing came off in the dip even when I shook it pretty vigorously. Any ideas of what I should do now? :hmm2: Just let it be I assume?

 

[phasezero]

Our green pociilopora frag has had it's base polyps slowly eaten away by a few large amphipods.

 

[JaneG]

Since this topic, the coral has just been weird. I moved it down - I think I was blasting it with too much light too fast considering where it was. It lost more polyps and I even saw some of the polyps peeling off like skin (RTN) but different. It is now on the sandbed and has remained the same (not losing polyps but I don't think it's gaining them) but is still getting a little brighter/deeper in color. I don't have high hopes for it.