eye swollen and sore

Question
I have a red ear slider well i have 3 all in the same tank 1 has it's eye swollen and sore looking it has gotten worse in the last week also her shell is discolored and dull. I read that you can put them in carrot juice will that work if the eye is an infection and is there something else i can do she is also not eating very well.

Answer
This turtle will probably die, and maybe the others with it without treatment. Carrot juice and other such nonsense is not going to work. You need a vet. You have provided absolutely no background info as requested in my instructions, and I don't have the time to make guesses about what you are or aren't doing right. You wrote two sentences, and it takes a little more than that if I'm supposed to make a diagnosis or offer advice.