Kessil

Reminder to All: Acropora Eating Flatworms!

I just had my first experience with Acropora eating flatworms (AEFW) this evening. They came in on frags from Diablo Corals. I don't mean to bash Diablo at all. In fact, I will call them tomorrow to tell them they have these in their tanks, just in case they don't already know. It seems that pretty much everyone who keeps Acros eventually runs into these little SOBs.

In case you don't know what they are, here is a Reefkeeping magazine article on AEFWs: http://www.reefkeeping.com/issues/2007-09/mc/index.php.

Two of the three Acro frags I picked up last weekend from Diablo seemed to be doing poorly. Then I noticed these bite marks, characteristic of AEFW:
IMG_1183.JPG

These little white disks of missing tissue are all you're likely to see on an Acro infested by AEFWs. The flatworms are so well camouflaged against the background of the corals skin that they are nearly invisible. However, noticing that these bite marks were spreading, I dipped the two affected frags in tank water + Gram's Iodine solution (essentially identical to Lugol's solution) for 5 minutes. Guess what fell off?
IMG_1179.JPG

The culprit! This was the largest of the AEFWs; it's about 8 mm long. The others were as small as 2 mm long.

The biggest problem with AEFWs is that even after you remove them with a dip, like I did, they aren't gone. By the time you find them on your corals, they have almost certainly laid egg masses right at the base of the living tissue of their coral host/food, or on exposed skeleton spots on the coral. The eggs are almost impossible to kill via chemical means without also killing the coral but, if you look very carefully, you can find them and scrape them off with a razor blade. I looked and at first I couldn't find any on my frags, but then I noticed tiny little patches of sub-millimeter diameter reddish-brown eggs. These things are HARD to see. I scraped several egg masses off my frags. Here is a pic of the same large AEFW from the previous picture with two egg masses near it:
IMG_1186.JPG

The AEFW is in the middle and the egg masses are on the left and right of it. All three of them are EXACTLY the same color as a browned out coral. Hopefully I have rid myself of these pests, but I'll be keeping a close eye on these frags for the next few weeks to see if more bites start appearing.

One more important thing to note: because I strictly quarantine ALL new arrivals to my tank, including fish, corals, macroalgae, and even rock, this will not affect the corals in my tank. In case anyone out there isn't running a QT, here is just another plug for setting one up and using it religiously! A 10 gallon QT saved the corals in my main system from this evil pest! At worst, I only stand to lose 3 frags. Without QT, I could've lost all my Acros! Admittedly, that wouldn't be a ton of them at the moment, but the point remains!

Have a good week everyone, and watch out for AEFWs from any source, but especially from Diablo at the moment.

Best,
Gabe
 
Ive seen these at most stores. Local fish stores bring in way too many livestock to prevent the introduction of pest species into the stores tanks. Theyre all businesses and their game is to bring in livestock relatively fast.

All the good stores including diablo corals dip before putting them into the tank but dipping only works on the adults usually. Eggs including flatworm eggs are mostly unaffected by dips. Stores simply dont have the time and cannot afford to hold corals in quarantine tanks before selling.

But they try their best, pre dipping, post dipping, pest eating fish, etc.
 
Last edited:
Eggs are almost never on the clean live coral. frag plugs, live rock, dead coral... all can host eggs and other pests like unwanted algae. I would re-frag anything I put in my tank(not that I would put anything new in anyways) :)
 
^^ Same boat. I chop off the bottom cm + the plug. Too bad so sad. I will keep adding things until it looks as full as your tank. If I can't catch up in growth, I'll juice the tank until it looks like yours! Frags on frags on frags!
 
Dude i straight take the frags off the plug if i can. Either bone cutters, chisel, or dremel it off. Never know whats growing on the plug. Also it exposes the corals crevices/underside to the dip.
 
Update: I called diablo and they reacted positively. They said they've been getting in new maricultured pieces in preparation for their frag swap and have been hoping to avoid these kind of pests. They asked me which tanks the infested frags were from and said they would redip everything and try to get rid of them. I just thought I'd let the rest of you know about their response.
 
Update: I called diablo and they reacted positively. They said they've been getting in new maricultured pieces in preparation for their frag swap and have been hoping to avoid these kind of pests. They asked me which tanks the infested frags were from and said they would redip everything and try to get rid of them. I just thought I'd let the rest of you know about their response.

Interesting. A simple dip and quarantine procedure could have prevented their systems from being infected. Doing anything seems better than knowing that they are totally at risk and just "hoping" that they don't get infected. If they had AEFW and didn't realize it, it's kind of embarrassing for them. If they knew that they had AEFW and didn't do anything to stop spreading it around, it's pretty evil. It's been a while since I've been to Diablo, but aren't their systems all tied together?
 
There aren't really any stores you can buy guaranteed pest-free corals from. All it takes is one or two eggs to survive the dip and then bam. Your systems infected. That's why dipping corals no matter who or where it comes from is imperative.

I really need to set up a quarantine tank but damn, it's one more tank to take care of :confused:
 
There aren't really any stores you can buy guaranteed pest-free corals from. All it takes is one or two eggs to survive the dip and then bam. Your systems infected. That's why dipping corals no matter who or where it comes from is imperative.

I really need to set up a quarantine tank but damn, it's one more tank to take care of :confused:

Eggs ALWAYS survive the dip. All you have to do is dip the corals initially, put the corals in a separate holding tank for a few days until the eggs will have hatched, and then re-dip to kill anything that hatched (before it matures and starts laying more eggs). I think AEFW hatch in 5 days. I don't really think that it's asking too much for a LFS to do this minimal amount of work before corals go for sale. This goes especially for anything maricultured or cut from a wild reef - that shit is almost guaranteed to be infected with pests.
 
There aren't really any stores you can buy guaranteed pest-free corals from. All it takes is one or two eggs to survive the dip and then bam. Your systems infected. That's why dipping corals no matter who or where it comes from is imperative.

I really need to set up a quarantine tank but damn, it's one more tank to take care of :confused:
FYI
Eggs survive most dipping as far as I know.
 
For the record, the guys at Diablo did say they dip all new arrivals. I guess they don't have proper QT for corals at least. I think they thought they got all the pests like AEFWs. I don't think they were intentionally not treating their corals and spreading pests to their customers. I got the feeling that they were going to do something about this problem now that they know about it.
 
Dip everything! I was trying to find a funny meme about dipping corals but there wasn't any.

Yeah Jess at DC is a super nice guy and very knowledgeable.
 
Last week I got a Mille from Neptunes and went through the same trouble :( I couldnt notice any dead tissue at the store but closer inspection before my dip, I saw a small portion of skeleton and knew something is wrong.

Dipped in Coral Rx and within minutes I got 5 AEFWs!!! Did some reading about the eggs, inspected closer and didn't find any. I removed the frag from the plug, glued over & around the dead tissue & entire base and stuck on a piece of rubble, dipped again for longer in Rx and then added to my DT. I hope no eggs made it in!!!

Here's a macro pic of the AEFWs I got rid of!

AEFW.jpg
 
Also wanted to mention... I called Neptune about the AEFW and was clearly told that they DONT DIP anything that goes into their systems.
 
Yikes Nav!

I hope you're lucky and really did get all of them before the frags went in your DT. I somehow doubt that a coral with 5 of those bad boys on it didn't have any eggs. Hopefully the eggs were on the base of the coral or frag plug that you removed. Nice macro shot of our mortal enemies!
 
Back
Top