After initial opening, how long will this last in its covered bucket?

Hi Finn, thanks for the question. Many factors determine how long the primer will last after it has been opened, Some things to consider are how much product was used, the amount of air in the container, if the lid is tightly sealed, and the temperature that it is stored in. You can check to see if the primer is still good by giving it a good stir and smelling it to see if it has an odor. If the primer is the right consistency and it doesn't have a foul smell, it should be ok to use. Have a great day! -Ronald