I've had my two turtles for over a year now, They've had this for sometime, at first I thought it was shell rot, then bacteria. I dry docked them for 3 weeks well add betadine and anti bacterial cream. After that it seemed to for the most part have gone away. Now its back and Im unsure as to what it is and the best way to cure it. They don't act any differently and they eat well.
My turtles are about as big as my hand
I've had them for a year
water roughly 78 Degrees
I have a heater set to this number, no thermometer
The tank is 70 gallons and its about half full, so it has roughly 40 gallons
I do not use a water conditioner, not sure what this is.
I have two whisper i20 water filters
Not sure of the basking temperature
I have a 100w basking light
They can climb on the dock easy, its big enough for both of them and I see them on it all the time
its made out of Plastic
I have a UVB Light on the other side, lighting the tank
I successfully feed them pellets, lettuce, berries, and from time to time dryed shrimp
They eat once every night
About 70 Gallons
A window is above it
The tank is in my room. Beside my desk where I am a lot of the time
I have read the basic care section
I have searched and so far nothing worked permanently
From what I can see there are no other unusual symptoms

- Bottom of Turtle Shell