The "chalk" look may be residue left from the wood cleaner. We would suggest using DEFY Wood Brightener at this time followed by a thorough rinsing. Once the wood is dry after this, the gray color should be gone. The DEFY Composite Waterproofing Sealer is completely clear and the wood color will not be changed. However, the DEFY Wood Brightener should help restore the look of the wood.