You can use oxalic acid when trying to remove discoloration or water damaged spots. The entire surface needs to be treated and then neutralized with a clean water wash. Mix 4 oz. per quart of warm water. Wipe the entire surface down with the mixture and allow to dry completely. Rinse table with a clean damp rag. Finish sand with 180 grit followed by the final sanding schedule below. Make sure to wear a dust mask when sanding wood treated with oxalic acid - the dust can irate the nose.
Lastly, finish sand with the appropriate grit paper:
- Oil-based products: 150-grit
- Water-based products: 220-grit
It’s not a bleach but it will brighten the wood back to its original color.