Fenbendazole And Snails- A Cautionary Tale

  1. Mazeus

    Mazeus Well Known Member Member

    Hi all

    I had a hydra infestation in 2 of my tanks (my 5g and my 15g). I had planned to turn the 5g into a shrimp tank (which I have now done) and the 15g had fry and tiny fish that were getting stung by the hydra. I tried a few ways to get rid of the hydra naturally, but alas it didn't work so I decided to treat with pancur (fenbendazole). I knew there was a risk to snails with this treatment so I moved my mystery snail and my spixi snails to a qt tank while treating. Once the hydra was gone I did a big water change and added carbon to the filter to clear the remaining meds. After a few days I added the snails back in to the 15g. The mystery snail appeared to get more and more lethargic, eating less even when I put in his favourite foods. There was a gradual decline over about 1-2 months.

    In the mean time I also converted the 5g (which was a well established tank) into a shrimp tank. I also added a nerite. From day 1 the nerite was withdrawn. I had it for about 9 days and then it died. Today my mystery snail has also died. I've also found empty pest snail shells throughout both tanks since the fenbendazole treatement, so I believe these deaths are connected.

    I'm sad and frustrated. I used the qt to avoid harm to the snails, but I'm wondering whether some of the meds leached into the substrate or silicon.

    If I could turn back time I'd remove all the fish and use heat, but I thought quaranteening the snails would be easier. I guess i was wrong.

    I will be keeping a close eye on my spixis as I don't want to lose them as well, but they have been acting strangely, so I fear them may also be impacted.

    If you have hydra and you have special snails I would strongly advise against the fendendazole treatement.
     
  2. Gypsy13

    Gypsy13 Well Known Member Member

    I’m sorry about your snails. :(
    Unfortunately, and sadly, I had to use panacur to remove pond snails from a small pond once. Easiest way to kill them all. They were carrying a viral bacterium and I had to kill them. Broke my heart. Anyway, that’s why I’d never recommend fenbendazole for any tank with snails.
    To make sure it’s completely out you need to run the carbon, water changes and heavy substrate cleaning. Good luck. :(
     
  3. OP
    OP
    Mazeus

    Mazeus Well Known Member Member

    I had done water changes and run the carbon, the problem is I run heavily planted jungle tanks. To clean the substrate I would have needed to dig up so many plants. Although,I would have done it had I known, that mystery snail was my favourite. I thought QTing the snails during treatment and then using carbon would be enough. Boy was I wrong. Lesson learned!
     


  4. Gypsy13

    Gypsy13 Well Known Member Member

    Yeah, the worst part of this med is it floats right on down to the substrate. Even when it’s medicated food. Great for killing snails you have to kill. I’m sorry about your favorite snail. People laughed at me when I lost my apple snails. They were old. Barney’s shell was bigger than a softball. More like a grapefruit. I want so bad to go out and get another but they’re an invasive species here. You can “harvest” as many shells as you want but you can’t tak it home alive. :(

    Which brand did you use?
     
  5. OP
    OP
    Mazeus

    Mazeus Well Known Member Member

    Thank you for your kind words about the snail. I love mystery snails, they have such personality, I can only imagine that the larger apple snails are equally as personable.

    I used Panacur (I'm in the UK). There is so much conflicting information out there about the treatment. I read a few times that it was snail safe, and it certainly isn't.

    Sometimes we have to learn lessons the hard way in this hobby.
     
  6. Gypsy13

    Gypsy13 Well Known Member Member

    Too true. How could you know it’s an extremely effective snail/slug exterminator. You couldn’t. :(

    For panacur, do frequent water changes. Run your carbon. Our research gave us half life of thirty to sixty days. Depending on the substrate. Now of course we have so many different substrates. The more absorbent the substrate the higher the concentration. I’d certainly wait at least sixty days before you try another snail. A pest snail. Though I’m fairly certain it’ll be ok. Keep us posted? Please?
     
  7. OP
    OP
    Mazeus

    Mazeus Well Known Member Member

    Thank you! That is very helpful information. I will.