Good thank you , been since 19th last post !
Can you post any pictures of their claws to tell? If both at the size in other photo should be able to tell. Short even claws is female then long uneven claws male in the front.
May want to wait on building anything until sex known for sure. One day you may need to separate them ! Even a 1000 gallon they will mate then you have to deal with up to 20 babies ! Or Female will "Hurt" male if she does not want to mate ! Also if two male's and have lots of hiding spots they could always fight . Hard enough with two to care for you may want to rethink 22 !
May want to backoff some of the papaya read this :
http://redearslider.com/plants.htmlJust a note ; to check a turtle always better out the water and when totally dry to check them. Will show all better if problems.