Filler marks on timber floor

I don't beleive it is the final finish that is causing the filled area to show. The Polyvinyl acetate (White Glue, Carpenter's glue) will darken the saw dust. By darkening the wood with stain this should lessen the visibility of the filler. It will still show, but by adding moisture to sawdust it makes it darken and locks it in as it dries.

hi woodman58, thanks for that but the filled area is lighter than the sealed floorboards.I've prob used too much filler and this has spread round the holes. I,ve only done half the room so happy to sand it all again.Can you suggest a stain, would actually like it a bit darker cause it,s in a 250 yr old stone house and the finish at the moment looks a bit 70,s. I,ve used dark liberon wax polish before in a previous house and liked the finish but thought the granglaze would be more hard wearing and less maintenance.I want to get it right cause this is the main living room but I also have the whole upstairs to do as well. Thanks

I assumed that the glue would darken the sawdust. Sorry! If you use Cyanoacrylate (super glue) it should darken the sawdust. Then add the stain of your choice. I don't have a preferance. I do like a gel stain for furniture but, it would be expensive for a floor. As for the final finish, I only use a poly for floors because of time restaints. I like a lacquer finish for furiture.