Can I use Aquadefense on this? Do I need to prime before I apply Aquadefense? Or do I apply waterproofing before self leveling?

Thank you for your inquiry regarding MAPEI Products! The layering system is as follows when using a Self leveler. You will need to prime the existing substrate first, then pour your Self Leveler. Once cured, you can use the Mapei Aqua Defense over the cured Self Leveler. Please note, Self Levelers cannot be used in a wet area or on a shower floor, therefore we are concerned as to why you are using the Mapei Aqua Defense and for what purpose. Please consider calling us here at Tech Support for additional assistance with your project before you begin. Tech Support can be reached Mon-Fri from 8 am to 5:30 pm EST at 800-992-06273. Thank you! Product Advisor # 11