Amphipods eating coral

[Scott48]

I picked up two acans from ARC and i fed the one mysis and it ate it and was all out and looked awesome, the next morning both acans were completely closed, well i figured they were digesting so that night i looked into the tank with a flashlight and there had to be 10+ pods on it and their HUGE, and it looked like they were eating it. The next morning 1 small baby head was gone out of the 3, this continued for 3 days, every night they were on there, and every morning less and less until now and its completely gone. I also saw two on a paly at night and the next mornig half of 1 of the 2 polyps were missing. Whats going on? Thanks
Scott

[toddmh]

wow never heard of this before lol but I'm kinda new at this ...Go get a Mandarin-fish,he will take care of those pods..But also try to get it to eat prepared food..These have a habit of starving with they wipe out the pod population..

[Gary Majchrzak]

I've had thousands of large amphipods over the course of many years and I've never seen any of them attack a coral. How did you arrive at the conclusion they are amphipods... how did you ID them as amphipods? Is there a picture online that you used or (better yet) do you have a pic of these coral munchers?

[Scott48]

Todd-I have a male female pair of mandarins which are now really big and have had them for about a year and they eat mysis and there is a huge amount of pods in my tank everywhere you look there there only at night though.

Gary- i dont have a good camera but they look exactly like this and this

[Scott48]

The only thing different is they have a white line along the division between each segment

[Dave VG]

Could they be nudibranches of some type?

[tmz]

I've never seen or heard of an amphipod like the picture eating coral. As Gary noted they will clean up dead stuff including uneaten food.. Do you have any peppermint shrimp in the tank? They mess up acans, zonathids and micromussa ,ime.Beyond that I'd look at water parameters including temp swings. A dip in Revive might help in case there is some sort of micro predator buffing them.

[Gary Majchrzak]

those pix don't look anything like a nudi

I've seen pods eat the dying flesh on corals but never healthy tissue....

[aww_419]

Shot in the dark but, small iso-pods , maybe???

[GMaquarium]

I have never had such problem, but this is not first time I hear about it. Perhaps with such high population and lack of food these guys are getting brave. Brave enough to go steeling food from corals and possibly eating to coral too. I would look into adding a predator to cut these guys down or feeding the pods more.

[Scott48]

i mean they were definately eating healthy tissue and i already have two large mandarins in my 75 and there still a huge pod population and theres no peppermints in my tank just cleaners, a blood shrimp and a pistol. The temp stays around 88-89 all day and night. I remember feeding my acan at night a mysis and i saw the pod hauling the shrimp triple the size of him off it maybe they figured thats inside the acan? idk but theyre destroying things and i really hope they dont get to my campfires.

[Jacwil]

Wait... what are your tank temperatures?

[Scott48]

78-79 srry

[dan10342]

I've had those things u pictured munch on zoos before, but never acans... weird

[Scott48]

ya theyre absolute monsters i saw one on a chalice too next mornig skeleton was showing on the side they are absolute monsters i just got a scooter to try to cut the population down, it should eat the smaller ones.

[Scott48]

Bump...

[tmz]

Amphipoods are scavengers. Some may have carnivorous tendencies. If you want to know more about them you can google search under the following suborders: Caprellidea, Gammaridea, Hyperidea, and Indolfielidea. Those pictured in your post are Gammarids. They are considered beneficial to a aquarium since they quickly and efficiently eat rotting organic matter.They are noted to eat detritus,algae,bacteria, fungus,as well as plant and animal remains.

This from Calfo and Fenner,Reef Invertebrates, pg 300. ...they are often blamed....for attacking live corals...This is highly unlikely...as the amhipods are almost certainly simply scavenging about or consuming dead and dying material..."

So while it is very remotely possible that some variants may be carnivorous at times , it's much more likely something else is killing your corals.

Many have reported acan and "chalice" decay and death particularly with Austrailian species and attributed it anecdotally to some unseen micro nudibranch or bacteria. Maybe the pods are eating such a bacteria. Some have anecdotally reported succsess with interceptor treatments in these situations.

I've never heard of palys being affected . This leads me to think it may be some critical water parameter or a temp spike,. Perhaps even a toxin(metal etc).

I'd do a series of 25% water changes, run gac, and some polyfilter and dip ailing specimens in a lugol's bath and a Revive bath.

[OCRick]

I wouldn't doubt it, I've also had amphipods munching on my healthy zoos.

[St.james of reefdom]

From Advanced Aquarist.....
Copepods, amphipods, isopods, ostracods:

Certain species are parasitic and predatory. Some may form galls in coral tissue and may or may not be true parasites like the gall crabs. Many are merely commensal, living on coral mucus and associated flora and fauna. As such, they may be performing a cleaning function.

Hyperia galba amphipod predatory to coral tissue

Paramphiascopsis sp. parasitizes from a pocket formed in the tissue of gorgonians

Paramolgus antillianus associated with Ricordea florida

Acontiophorus bracatus ectoparasite of gorgonians, Leptogorgia, Eunicella and Paraerythropodium spp.

Asteropontius corallophilus parasite of Pocillopora, Montipora, Stylophora and Porites spp.

Asteropontius longipalpus associated with Ricordea florida

Asterocheres scutatus parasite of Rhodactis rhodostoma

Lichomologus spp. 6 species parasitic to octocorals, 3 species to fungiids, 7species to octocorals and stony corals, 5 species withPalythoa spp., 2 species with Rhodactis spp., 2 species with Psammocora spp. , 10 species to stony corals.

Acanthomolgus spp. 4 species parasitic to Atlantic gorgonians, often species specific

Psuedanthessiids spp. true parasites for all species in this genus

Rynchomolgids spp. true parasites for all species in this genus

Notodelphyids spp. some true parasites of octocorals, Paraerythropodium sp.

Xarfia spp. copepods with worm-like bodies and reduced legs that are parasitic and live inside coral polyps.

[St.james of reefdom]

Tried to find pics but didnt have the time ..try googling them

[Gary Majchrzak]

I have no doubt there are amphipod species that prey on corals but they're rarely seen in the aquarium trade.

I'm sure that the corals being munched in this thread are Protoplaythoa and not Palythoa, right?

[dadoftwins]

it could be that the pods are after the food your feeding the corals ..just a thought..

[tmz]

Could be some form of parasitic pod but I wouldn't overlook other possible causes related to the water, particularly since at least 3 species of coral(acans, challice and palys) are waning. Maybe some type of pod comes in with the Aussie corals, which would explain some of the success stories with interceptor since it attacks the nervous system of animals with ectoskeletons and will kill all the pods ,shrimp and such in a tank. As big as the acan craze is/was, I wonder if anyone has taken a microscopic look at ailing tissue.

Thanks for post St. James. Good to hear from you. Do you have a link for the article?

[Dave VG]

Tom has some very good points. I don't think anyone really knows everything that goes on in our tanks or all the possible predators that can make there way into it. With corals coming in from new areas and being kept in holding tanks with god knows what in them who really knows. I have googled this and scott is not the first person to have this problem. Hmmm. Never say never. JMO

[Scott48]

i tested the water and the only thing a little high were nitrates everything else was good and i monitor temp and its pretty constant

Gary- their reg. palythoa, looked like AOG's but pinker.

They only went after the one left the others alone, the things they went after though i got all in the same day but from 2 seperate places the 2 acans and a chalice, whilw they left alone and still are my other 3 acans and 2 chalices. i have seen tho one or two amphipods on my campfires and in my watermelon zoas ater the acan was destroyed, but i havent seen any damage yet but the one paly being attacked is now down 2 1 polyp from 4.

Tmz-they are Gammarids as you said but these corals were perfectly healthy i put em in my tank and they were fully opened and perfect, but there is a possiblility it could be something microscopic but again it really seemed as tho the pods were doing the killing, they were ripping at it with their front arms a lot.

Thanks for the help everyone still its just something that shouldnt happen and i got lucky to have it happen lol