Be careful with that Rust Mort. Looking at the data sheet, it states that it's main ingredient is phosphoric acid.
That is the main ingredient of OSPHO.
You run the potential of adhesion problems if you apply epoxy primer over a
surface treated and left with that type of rust convertor.
You could apply a Rustoleum type primer over it but that will not provide the adhesion and moisture blocking properties that epoxy primer will provide over a properly prepared substrate.
