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Anchor worms and fenbendazole

9977 Views 25 Replies 8 Participants Last post by  150EH
Over the last couple of months, I've noticed that my Gertrudaes will occasionally flash against plants. They don't do it often, and I was seeing no other indicators of disease so I decided to wait it out. I don't like treating something if I'm not sure what it is.

Today, I noticed a "tag" on the tail fin of one of the males. It's virtually impossible to take a decent picture of them (especially considering the only camera I have is my Droid), but I believe it could be an anchor worm.

Before rushing around and panicking about it, I wanted to ask a question: Will these things not like fenbendazole? I have it and I'm going to treat the tank for hydra anyway. I have nerite snails, RCS, and CRS in this tank, so I don't want to go bonkers on medications if I don't have to. I know I risk the nerites, but the original plan was to remove them. Now I think I'll just risk them for fear they carry the anchor worm.

I can pull the Gertrudaes out if I have to, they aren't too difficult to catch, but the otos on the other hand are a pain in the neck. Without completely ripping out all the plants and wood in my tank, it's pretty much impossible to catch them. Seems like they could have it too, but I've only seen one tag on one fish so far.

I figure practically any medication for this isn't invert safe, and there is clearly no way I'll get all the shrimp out to move them.

I need to start dipping plants. I haven't done that, and plants are the only thing new I've added to this tank in the last four or five months. :angryfire
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Looks like I'll be figuring this out on my own I guess. I read in a couple places that fenbendazole is supposed to work, but not many. It seems prazi (which uses another dewormer) is more popular, but I'm not sure it's safe with the shrimp and what not.

If it doesn't work, it looks like my plans with my 10g are going to be put on hold because it'll turn into a hospital tank for the fish. Then I'll treat with whatever I can that's in my arsenal. They will stay in the HT for at least four weeks, possibly more, before being placed back in the 29g. By then, I'm assuming all the residual parasites will have perished without a host.

I'm hopeful my fish will recover fine. Other than the occasional flashing, they are perky and active with great appetites. They look pretty healthy otherwise.
I thought anchor worms are actually crustaceans. I've read about people pulling them off with tweezers though I'm not sure how they got the fish to hold still.
There's no harm in trying fenbendazole. It kills hydras which aren't parasites, so why not anchor worms? If it works for you, be sure to post your results! Fenbendazole also works to kill camallanus worms (after they've been paralyzed by levamisole of course). It's kind of a miracle drug :p
I think the people manually removing worms are from like koi and other pond fish, because it's more something you see in ponds. There is no way I'm going to be able to remove some tiny little worms from a fish that's an inch long and has virtually no substance to it!

We use fenbendazole to treat our cattle, and one of the parasites it's effective against is ironically "anchor worm". It's not the same thing as what's on the fish, but I thought it was funny. I actually don't care much for fenbendazole with normal deworming of livestock. It works great if you need to slam the animals because you can virtually not overdose it in large animals. You'd need to give them like 600 times the "effective" dose to even start affecting the animal.

I figure since I'm going to treat the tank anyway, I'll see if it'll work. I'm pretty sure the parasites aren't going to care for it at least, so if it doesn't work I can move them into the hospital tank and start hitting them with stronger doses of anti-parasite drugs (which will hopefully do the bugs in). Fortunately, all of them will probably fit pretty comfortably in a ten gallon. Also to my luck my LFS has a "fish vet" that comes in handy during times like this. If anyone would know of any medication that would do the trick, he would. If I had to, they would actually take my fish and treat them over there.
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Ok, started with approximately .2g for my 29g tank. The Gertrudaes are actually eating it... A couple aren't spitting it back out, either. That stuff has to taste nasty. Strange little fishies, I hope they don't die from that. If this dose remains ineffective for the hydra, I'll add a little more tomorrow. So far, no one seems effected (not fish, shrimp, snails, or hydra). I don't have planaria in this tank, so they aren't exactly an indicator (all planaria has served as food for the Gertrudaes, who truely do eat anything that will fit in their tiny mouths).
Thought I would give a little update on the status of things.

Hydras still aren't dead. They don't look happy with the world, but most of them are still there. I put a tiny bit more fenbendazole in the tank.

Fish are still plucky as ever. If anything, the Gertrudaes seem to have more energy than before. The single fish that has a worm "tag", still has the worm. BUT, I noticed the worm changed colors. It went from being white to a greyish-brownish color. Hoping that's a good indicator that the little sucker doesn't feel too well.

The RCS, CRS, nerites, and otos all seem peachy. In fact, I think one of my CRS is berried now. Hard to tell, I have two females in a 29g tank and they are really shy, so she was trying to get out of sight of me pretty quickly when I noticed her.

Treatment will continue par course until Sunday, which is water change day. I intend on not adding anymore fenbendazole to the tank for a whole week, then repeating treatment.
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make sure when you do you water change you vacuum out the gravel really well. Fenden can linger in your tank if you aren't careful. You can also run some carbon in your filter for a few days/week. I would observe your tank for at least a week before dosing any more.

Fenben also seems to have an effect over time. Better safe than sorry.
I would say this treatment has been successful! As of today, I can no longer spot any hydra or anchor worms. The single tag I could see turned a funky shade of dark gray-brown yesterday. Today, the fish does have a small white dot where the worm was attached, and I'll be watching him closely to make sure he won't form another infection. He's pretty easy to identify; he's the dominate male in the tank and instead of having yellow pectoral fins, they are light blue.

Zero casualties. Everyone seems pretty happy, and the Gertrudaes really do have more energy. I've been monitoring the tank closely to make sure no one starts going lethargic on me and keeping my back-up hospital tank ready in case anyone needed a quick break. But it seems everyone handled the treatment great and even the Zebra Oto is happy and energetic.

Today, I'm doing a 50% water change and running activated carbon in the filter to remove the rest of the fenbendazole. There is no way I'm going to be able to vacuum the gravel; so I'll be running the carbon until next treatment.

I'll be doing another dose of treatment in two weeks from the starting day of this one. I do not want to take chances with eggs and further stress my fish. I will dose less than I did this time, and put the powder in the toe of some pantyhose to keep from having a white powder fly all over the tank. My fish showed no ill effects from eating the fenbendazole, but I'd rather not let them no that again. I'm pretty confident these guys have no worms now though :hihi:
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Fenbendazole is a beautiful thing! And it has a short period of being effective. I've seen written that after 48 hours exposed to light it is 10% as effective as when it went into the tank, and by 72 hours it's basically inert. I just do a 50% water change after dosing, and that's only to make sure the dead planaria or hydra don't cause an ammonia spike. I don't think bothering with carbon is necessary, I've never had a problem with not using it.
From watching the hydra, I'd definitely say it still works after 48 hours. It took the hydra 72 hours in total to die, but I did add more fenbendazole on Friday. I do think it loses it effectiveness fairly quickly, but I decided to run carbon as a precaution. It won't harm anything, even if it's a bit overboard.

It works, that's for sure. I wonder why there isn't more info on it against anchor worm, though. Considering anchor worm isn't typically found in aquariums, but it's a pretty common ailment in ponds, I guess it could just not be economical. It would take a great deal of fenbendazole, working with something you can't just change the water out of. It's probably less effective than other treatments and manual removable in such a setting. But when working with a densely planted fairly small aquarium, that houses several sensitive inverts, and working with tiny little nano fish, fenbendazole seems to work great.
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I have a Kribensis with a big worm in his forehead and a small white circle on his flesh at the point of attachment and I'm almost sure it's Anchor Worm. Were can I get Fenbendazole and is it a Aquirium product? I see it is sold for deworming dogs and cat but how would I know how to dose a 150 gallon tank?????
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Please be careful with fenbendazole! It is a good medicine, but it can also poison your fish if not dosed carefully. flubendazole is much more efficient as it dissolves better in water.

I am talking from a recent painful experience: Total death toll: 42. So, just be careful if you use it.
Well that still doesn't answer any of my questions, you must have overdosed as well??? Ineed to know under what brand name do I buy this and at what dosage do I use it and how frequently????
I also wanted to add this, the suspected Anchor worm starts right in front of the top dorsal fin and it seems to be the same coloring as the fish, plus it doesn't lay over but stays erect as he swims but it does have a small white area at the base. I just want to be sure before I treat anything.
I used 1/2 the recommended dosage. I got it at the petstore, it's called Pancur or Safeguard. its a dog dewormer. It doesn't dissolve well, so if your fish eat too much of it, it will poison them. You use .1 gram for each 10 gallons of water and change the water a good amount to kill planaria and hydra.

For deworming fish, I'd get a legitimate medicine. Here are other examples of problems.

However, if you still want to try it, here is the instructions:

Actually Jungle Brand Parasite Clear did very well for external parasites like anchor worms for me in the past and it is much cheaper, can be found at Walmart and petstores. Isn't shrimp safe.
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If you are sure it is an anchor worm, why not just net out the fish and pull it off with some tweezers? I have done that with a couple of anchor worms on Pearl Gouramis and that was all that was needed.
Thanks for the info, I did find Pancur but you need a prescription and Safe-gaurd I can get a Petsmart. I will take a look at the other cures and info thanks again for your help. I would also appreciate more info from anyone that has hadan experience with any of this.
Another option is to get meds sold to cure anchor worms at the local fish store. They come in a nice package and portioned out for you so you don't over or under dose.
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