Is grain filler required?

Q: Is it required that I apply Grain Filler to my wood floors before finishing them? I used sanding sealer on a test piece, lightly sanded to knock down the grain, and sealed with two coats of Oil-based Polyurethane. The majority of the wood is shiny and smooth, but I can still see the grain in the finish.

Is this normal/acceptable, or do I need the Grain filler?

A: Yes, this is normal. If you didn’t want a heavy grained wood, you should have chosen something like maple. While much experience goes into sanding and finishing a hardwood floor, regardless of species, you should not expect it too look like a grand piano. If you are working with oak, you can’t just make the grain go away.