RES are highly prolific and will adapt to almost any condition given, as long as they have water shelter, and the right food. They do just fine. The only thing that is sometimes difficult to get exact is the proper breeding condition. The RES can be picky sometimes. So breeding is not always as easy as it would be with land turtles. I have nothing in the water side for the turtles to submerge themselves in to or under. It sounds as tho you have the right conditions. so I wouldnt worry to much. You are definitely doing better than alot of individuals that buy them from the pet stores or flea markets as a quick pet.

Gary C.