We just noticed little worm looking things in our tank with the turtle. Wondering what to do and is this a concern for the turtle's health? We have had the turtle for about 6 months and he has been healthy so far. We do weekly water changes and the only things we have in the tank are 2 filters and a basking rock. They are hiding behind and under the filters except when they swim out and we catch a glimpse. I used my largest zoom on my camera to snap a photo. Any help would be greatly appreciated.

