Fenbendazole and snails

For the THIRD time, I’ve got hydra (oligactis/brown hydra, not the green type) in my shrimp tank. Probably hitchhiked on some new plants. Going to treat it with 0.1gram/10 gallon (38L) by dissolving safe guard dog dewormer.
From experience, I know that this is safe for larger pond snails and baby assassin snails. I’ve got some other snails now, which I haven’t tried fenbendazole with before so I wanted to hear from others how these snails do with fenbendazole.

-Ramshorn snails
-small/baby pond snails
-Malaysian trumpet snails

I can setup a temporary tank to move out all the snails I can find, but then when would I be able to add them back? Even with fresh AC, residues of the fenbendazole would remain. Should I dose less? If so, how much? So far I’ve only seen one hydra, small-medium size. Big enough for there to be more, and I have a few saddled and a berried female shrimp. No shrimplets yet though, and I don’t have any shrimp younger than 2 months.

 

You can take a chance and do half dose and leave them in, I hear conflicting reports on full strength so half dose should be OK, OR
take them out and still do half dose and with some good water changes you should be OK after 2 weeks

 

Been two weeks since treatment,
I did not remove any snails and did a bit more than half of a solution of dissolved 0.1 gram of 222mg fenbendazole/1gram powder. All hydra were gone in a few days and no snails were harmed by it. A momma had her shrimplets during the treatment as well, they all seem fine though and have grown much bigger since. Pond snails had a population boom during this time as well

 

Thats great news ,its strange how fenbendazole harms other tanks the only thing I can think of is the overdose thinking a little more won't harm them, how wrong could they be

 

not sure what it is, but I think it has to do with the type of snail. Nerites and mystery snails seem to be a big no-no. The only other thing I could think of is if someone used a dewormer that also contained ivermectin, but this would be listed in the active ingredients and is more used for horses than dogs

 

So its quite easy to buy the wrong fenbendazole