"add" like mix it with the paint?
Well i have some problems ... with the prosaide and Permawet ....
http://www.freebits....691100_1054.jpg
i got brown/green spots .....
Raw latex , prosaide, paint , prosaide, new layer of paint(other colour), prosaide and as last a layer of Permawet.
I force dry the paint & porsiade with hot hairdryer