If those “scratches” are straight lines that you can feel when you pass your fingertips over them then you are likely dealing with glass that was damaged on the cutting table. That’s really bad news because those scratches can easily break under pressure. I hope this isn’t the case but I’d get a new tank before I’d fill a large scratched tank in my house.Most of the scratches are fairly difficult to see unless you are looking very closely. Two of the bigger ones are near the bottom and pretty well hidden by the sand bed. There's just two that bother me, there's one on the front pane and one on the side pane, both a couple inches from the top. One of them is in the main viewing area, but the front is a 7ft long so it can be easy to miss. I think you're probably right though, I'm really not sure if it would be worth it