Sounds like a flame polish which isn’t the best.. the heat stresses the material and will most likely cause crazing down the line.. you can hand polish to a extent over a router cut but it won’t be pretty.You all don’t mean actual euro bracing right? The top should be a solid sheet of acrylic welded on to form a box with holes routed out.
Actually no, I just ordered an acrylic and only the corner edges came hand polished and it would have cost significantly more to get the bottom and top edges polished. The reasoning was that these are usually hidden. I was already into the tank at that point but was not thrilled when I learned that. They were able to polish the edges to make them gleam but they are not sanded so you can see the router marks.