Box turtles need high humidity, Around 70 percent or more, Sand is one of the worst things to use, you want to use soil at the least. Your turtle is wild cought, and a 20 gallon tank is way way way to small. You will need to build a big enclosure out back, im talking 20x20 feet, orntates are the worst type of turtle to have wild cought, they will always try and will escape if theres away, They are also one of the hardest to keep. Is there a place where you can rerealse the ornate? It would be best for the turtle and possibly save you some time and money. THe ornate can stress to the point of death, and parisites are a facotor with her. I would strongly suggest finding a safe spot for rerealse.