My turtle Phillip

Question
Hello,

Today I noticed a while, stringy substance coming from my turtles bum. I have 3 turtles and they share the same tank, and have since they were babies.
I have done some searching online, and so far I have been unable to find out what it could be. In order for a proper diagnosis I am aware that I have to get a stool sample, in which is going to take time as I have to separate my turtles to make sure I am getting the right stool.
I was wondering if you could give me more information on this, until I can figure something out, and if there is a treatment that I could purchase over the counter for my babies?
Any information would be greatly appreciated.

Thank You,
Amanda

Answer
I need more information. How big is hte turtle?
species?
age?
do you have uvb on them?
are you using heat?
temps of water?

this sounds like a fungal infection onset.

are you using filtration?

let me know the  above answers and ill be able to go further.