Yes, you can apply TotalBoat Halcyon over acrylic paint that has completely cured for at least 48 hours. Before applying Halcyon, clean the painted surface to make sure it is free of surface contaminants. Use 320-grit sandpaper and scuff the paint surface very lightly. Remove sanding residue, then apply Halcyon, as directed on the product bag or in the Halcyon Technical Data Sheet.