How Do I Get Rid Of....

[mrscrubit]

What are these black spots/stains? Is it tannin or old residue from a previous stain? How do I remove?

Story: Deck was originally stripped with Behr deck stripper, result was what you see here. Then did test spot with Cabot deck stripper with no visual difference and then Defy OxyBleach Deck Cleaner...still no visual difference.

Any help/suggestions are appreciated.

 

[john orr]

From what I see, the bottom board still has some old stain on it - cedar? Believe it or not, if you follow the direction on the Behr Premium stripper, it will remove the old stain. (Flood's stripper will also work - and smells a little better as well as sprays more easily through a pump-up.)

After stripping-off the old "stuff", neutralizing with oxalic will lighten the entire deck, as well as the darker areas that are not stain. Make sense?