Is it possible to remove a failed lesser genetic mutator philter from a sylesti? Just wanted to know because they keep doing nothing and it's starting to get on my nerves that they can't get anything now.

(Also, I feel like you should be told that it can fail when you read the description. It doesn't say it can fail anywhere.)

They aren't failing :)
a lesser genetic mutator can give carried or visible traits
carried traits are not seen on the pet but can be passed down to its offspring
visible traits are shown on the pets page by default but carried traits require genetic testing to be visible
If you'd like I could test your pets for you so you know what carried traits the mutator gave them
you'd need to set them up for 1 gold for sale to my user id
I would then buy them , test them and set them up for sale to your user id so you could pick them up

OHHHH- I didn't realize that the carried ones wouldnt show up. Thank you :)

And I'll set the ones I want tested up- thank you again

you're welcome :)
they're all tested and ready for pick up
https://www.sylestia.com/view/pets/?petid=8734934
https://www.sylestia.com/view/pets/?petid=8735505
https://www.sylestia.com/view/pets/?petid=8739125

Also as a side note if you get any traits you don't like you could also use a philiter of nullification (avail in the scale shop), though I do not think that gets rid of the mutator symbol if I remember correctly (when used on a tamed pet)!