I have 2 RES, 5 years old. 1 female who is about 7 inches, and 1 male who is about 5.5. My male started to bask for an unusually long period of time 2 days. When put back in the water he seems to sink, not swim. Although, he is able to climb back up to the dock. He also refuses to eat. He wasn't floating, and doesn't have bubbles coming from his nose or mouth or appear to have swollen eyes. My female turtle happy and healthy. I noticed the water temperature fell to 60F They are in a 75g tank. The water temp is now around 82. The docking temperature is about 89-90.
It should be noted, There have been some issues with my male since I got him 5 years ago. His ability to walk on land is strange, he seems to think he is still swimming and will take unnecessarily big steps on land. Also eating food that's held right outside the water, he will aim and miss, in the water he eats no problem.
I never really worried too much because he seemed to get along just fine with these quirks. He's quite skilled at catching feeder fish when they are given them, and always had no issues swimming.
I give them a diet of turtle food with calcium, shrimp, turtle treats and about once a month a few feeder fish.
How I should continue to monitor his behavior and for how long or at what point I should go to the vet?
