You need to cover three sides of that tank not the top of it, he sees out through the sides not the top. And if he went from a small little setup to what you have with no sides covered so he can see out he is going to stress for a couple days. You really need to cover 3 sides of the tank, for example when I changed my big guy Groot at the start of the month from his tengallon Into a 20 gallon high he buried for 2 days and then after that he would come up but every time I came towards the tank he would get scared and hop off to a corner, and he wasn't doing this is the ten. While this was happening I had 3 sides covered everything was spot on so I was stumped. So I measured the height of the glass on the front of the 10 gallon and lets say it was 12inches don't remember if that's what it was forsure, but anyway the 20 gallon high was like 18inches so I covered 6 inches across the top at the front to match the front of the 10 gallon when he was in it and that night he was back to normal. So I figured he was freaking out because now when he looked out he was able to see so more of the room and me when approaching the tank he really didn't like it. So again covering 3 sides does miracles and I imagine it will help, may not totally solve the problem but it will help a lot.