Please post pictures of the cloaca and the nails of the two turtles. We will be able to help you determine their sex
If this continues and possible injury might occur, seperate them no matter the sex.
ellman605 wrote:Use the aquarium rule (10 gallons for every inch....)
E.T
This rule is beneficial, but it is not completely necessary. Following this rule in some cases will be ridiculous. Turtles can thrive in gallons that are a bit smaller, and each new turtle should not be a result of adding how many inches and gallons to the tank.
I generally go by this rule for a single specimen - Gallon size
canbe .5inches smaller than the turtle
E.G. - a 4 inch turtle can thrive in a 35 gallon tank.
a 9 inch turtle can thrive in a 85 gallon tank.
But it is always important that the biggest enclosure you can possible get is better.
An additional turtle, no matter the size, should extend 30-40 gallon in the enclosure.