Acropora Eating Flatworms

Starting about 5 months ago, I had some corals that weren't looking well. Losing color, poor polyp extension, etc. I tried moving them around in the tank, that didn't help. I changed out phosban, carbon, lighting, religious WC's, etc. Still, they weren't doing much better, and others were flourishing. I thought that some were being affected by a nuisance algae, as they were losing color at the base, and algae was growing around and onto them and other corals.

Well, 2 months ago, I discovered that I had Acropora Eating Flatworms.

I took a once Yellow Tort out of the tank and under a bright light and magnifying glass, I discovered the eggs. This was confirmed by someone else also as being the AEF eggs. There were no signs of adults, which was expected as they are translucent and camouflaged on the coral. I then, obviously, left the coral out of the tank and it started to dry. After about 30 minutes or so, I could clearly see the adult AEF's on the coral. They started turning a brownish color. After 24 hours of drying, they weren't much darker and if you weren't looking for them, you might not ever notice them.

So I started researching the web to learn how to eradicate this pest. People have tried many dips, chemicals, etc, and while there are effective products out there, you can only kill the adults with some of these. The eggs are extremely resilient, and there is nothing known to us yet, that will kill the eggs. The only way to get rid of the eggs is to scrape them off (and they are almost embedded into the coral) or to let the life cycle continue (let them hatch) and kill them with the dip/chemical.

So with that in mind, here's what I have been doing since 2 months ago.

If you want to conquer this issue, then sadly, the only real way to do this COMPLETELY, is to remove every acropora from the system and put them into a QT tank. By removing every acro from your system, you are cutting off the food chain for the AEF. Acropora are the ONLY thing that AEF's eat. Without it, they will starve and die. Another reason for removing all acros from the tank is because even though you might remove, QT, and/or throw away any affected acros, there's the possibility that there are adults moving through the system (over rocks, in the current, etc).

A.) Setup a QT tank with lighting to support SPS. My QT setup is:
10g tank
1 - 150w halide 12" above the water
1 - Korallia 2
1 - Rio intank filter/pump
1 - 50 watt heater
1 - Frag Rack

B.) Revive Coral Dip
This dip is confirmed on the web and by myself, to work at killing the adults. CoralRx is also confirmed to work.

C.) White Dipping/rinsing bowls (Walmart $6.00 )
I use white bowls so that I can confirm that any adults that may have been on the coral have fallen off and are dead at the bottom of the bowl. This also aids in confirmation of no more AEF's if your strict routine is working.

I do weekly 5g water changes and top off daily as needed.

At the same time I do the WC, I use the old water to make the dip at the maximum dosage. I remove each coral one by one and inspect them under the light and magnifying glass for any eggs or adults. If eggs are found, you can scrape them off although I really found it difficult to do this. It is like they are embedded into the coral itself. I attempted scraping them off but gave up, and either cut a frag or threw the coral out. You can let the life cycle run (eggs hatch) its course and not scrape them off (which is basically what is happening anyways) and keep with the weekly dips to kill the newly hatched AEF's. I chose to throw them out if there were any eggs.

Next I sit the corals in the dip for a minimum of 15 minutes to a max of 30 minutes. During this time I use a turkey baster to lightly blow off the corals and manually "swish" them around.

If adults are on the coral, you will start to see them "jumping" off of it and trying to get away. This is the process of their death. (You can look on YouTube for videos of it actually happening as I did not take any video).

After the dip, and confirming that no other adults are falling off, I rinse them off, swishing them around in the 2nd container of used SW and place them back into the QT.

I check every day for any signs, but as mentioned, the adults are translucent and near impossible to see. Bite marks can be visible, but the AEF’s can be very very small, and you may never see a bite mark.

It's been 2 months now and out of 19 acros I have saved 9 of them from death. It's not an easy thing to remove the corals and throw them away, but all it takes is 1 AEF to start this downfall and the next thing you know there is an infestation.

At this point I have not seen any more AEF’s, and no signs of eggs. If I missed any in the display tank, they are long dead now. The first and second week of dipping I saw many flatworm casualties, and have not seen any since then, but they are small and I may have not seen them in the bottom of the bowl. I plan on doing this for 3 months total, maybe even longer just for peace of mind.

Another thing I did do was to add a Yellow Coris Wrasse as they are known to eat the flatworms. There are a couple wrasses that are a sure thing to eat the AEF, but they are hard to come by. Wrasses from the Halichoeres and Psuedocheilinus family are known to eat the AEF’s also.

I’m now 5 months into this since the issues first came about, and I’m happy to say that my surviving acros are doing well. If there were any AEF's or eggs left behind in the DT, they are dead for sure since I removed their food source completely.

In the future, I will be keeping a QT tank running at all times, and EVERYTHING will be in there and treated for 3 months before going getting an ok to go into my Reef.

Something else that you should do also. If you purchase a coral of any type and find that is has a pest, return to the LFS where you purchased it and let them know about it immediately. You will be saving your reef, of course, by not putting it in, and you will also be saving others from a possible infestation. Our LFS are outstanding when it comes to customer service, and I am sure that they will be happy to swap out the frag for something else, as well as attack a possible outbreak in their system/s.


This is the image of the underside of my once thriving Green Slimer. Eggs are all over it on the underside. I obviously did not see them as they were on the bottom of the coral.

It's a thumbnail, click on it and then zoom for the full size (1600x1200).

Great info! Thanks so much!!!

Here's a good youtube video I found: Coral RX Killing Flatworms - YouTube

Great write up!!! I have yet to deal with the dreaded AEFW - hope I never have to!!! So the Revive kills them - at least with dilligence you can wait out all the eggs to hatch, dip, and kill them one by one...

great writeup!!!!!!

Did you happen to take any more pics of your process?

Originally Posted by LadyOfIreland

Great info! Thanks so much!!!

Here's a good youtube video I found: Coral RX Killing Flatworms - YouTube

These are Planaria Flatworms. Not that having them is any better They will spread in a system in no time also if not eradicated at the onset. There are several proven tactics to getting rid of them, both chemical and natural (predator like wrasses). Flatworm Exit by Salifert works wonders on a system treatment scale, but IMO, you need to dedicate a full day to this (which if i did get them, I would) Thanks for the link!!

Originally Posted by estanoche

Great write up!!! I have yet to deal with the dreaded AEFW - hope I never have to!!! So the Revive kills them - at least with dilligence you can wait out all the eggs to hatch, dip, and kill them one by one...

Revive definitely kills the adults, as you will see in the 2nd video I linked below. It's a long video but I recommend watching it through as the hobbyist has a lot of details for viewers.

great writeup!!!!!!
Did you happen to take any more pics of your process?

Unfortunately, I did not, but the 2nd video shows pretty much the same process for dipping that I was doing, except that he used a clear container. White or clear, either one will allow you to see the AEF's coming off.

Here's the video, it's a Fauna Marine video, but clearly shows the AEF's coming off the coral. It will give you an idea of what to watch for when dipping:
Fauna Marin Pest Control.wmv - YouTube

Another video with good information: Identification and Treatment of Acro Eating Flatworms (AEFW) - YouTube

Something else I will say is that if someone mentions to you that there's a possibility of you having the AEF's (or any other type of pest for that matter), look into it immediately! I was in disbelief at first, because some of my acro's (green slimer) were not doing good, while others had never looked better (great color, long polyp extension, etc). This is sadly part of the process of them making their way through the system, they just weren't on every acro yet.

Just in the last week, 2 local reefers here also discovered they have AEF's, and even after I explained to one of them what to look for, he was in disbelief.

We have nobody to blame but ourselves if it gets out of control, and you will never be able to pinpoint who/where you get them from, unless you inspect the coral from the start, and perform good husbandry.

Awesome thread
I had to deal with those things before they are a pita

I started this thread on my local reef club forums, so as I respond to posts there, I will copy/paste and more information here also.
---------------

Getting frags from fellow members is the #1 reason for parasite transfer. We can even get parasites from stores we trust. In most cases, we get a new frag, go home, dip it and it goes right into our DT. We think that we got any type of pest by doing the dip. I myself and guilty of this. But believe me, this will never happen again. As I mentioned I will have a 10g QT setup and running at all times. Cost is minimal, peace of mind and my reef are priceless. My husbandry practices have changed now that I know the painstaking process that's involved with a system infestation.


On another note, I've received PM's about using Levamisol for a system treatment. USE THIS AT YOUR OWN RISK

While there have been reports of suscessful system treatments using it, you run the risk of crashing your entire system and starting from scratch. If you use this in your DT, then you have now turned you entire system into a QT. I have spoken to someone who tried using the Lavamisol as a dip in the past (not in her system), and even after religious dipping, she lost all of her Acros.

Is that $60 bottle of magic worth your entire system?

Stick with what we know is working with regular routine, change your husbandry practices, and you will save yourself the headache of starting over again.