Open the Watermark tab
In the side menu of the panel, click Watermark. Both account-wide switches work on every plan, including Free.
Turn the watermark off for everything
The Completely disable watermark on photos switch in the When to apply group removes the mark from all selection galleries. New photos go up without it right away.
Or remove it only from your recommendations
A separate switch, Disable watermark on recommended, removes the mark from the photos you starred as photographer's choice. That way you show your favorites at their best and keep the rest of the gallery protected.
Reprocess existing photos
Changing the settings doesn't automatically update photos already in your galleries. Click Reprocess photos in the bar that appears above the settings, or Reprocess all photos at the bottom of the page, and Picvelo rebuilds the previews in batches in the background. For large libraries it takes a few minutes.