Johnstone's Trade Sterilisation Wash is a water based solution for use on surfaces interior and exterior surfaces before a topcoat is applied. 

Sterilisation Wash is formulated for the treatment and control of mould, fungal and algae growth prior to painting. Can be used on any surface, including cementitious boards, cladding, concrete, floors, glazed tiles, hardwood, iron/steel and masonry.

it can be applied by brush and is extremely good for use under Johnstone's Trade Anti Mould Acrylic.