I have a captive bred black and yellow splash back dart frog that just sits in his water bowl and has stopped eating. I purchased this frog 4 months ago, and he has been active and healthy. The lack of appetite and the sitting in his water bowl started about 4 days ago. Physically he appears fine. I currently have him in isolation, a tank with a water bowl and paper towels on the bottom and plastic plants. He hasn't gotten any better. Any suggestions?