Product Use


Saturate render well at a 1:50 dilution. Green and red algae die within minutes of application and to maximise long term benefits the surface should not be rinsed and GK PRO should be allowed to evaporate naturally. Green algae will disappear first, sometimes leaving a faint shadow for a few days and, due the darker compound within red algae (beta carotene), this may linger for a while longer. Self-cleansing usually takes around two to three weeks. Some black marks from black fungal discolouration may still persist but will recede over time.

When GK PRO is applied to saturation it kills biofilm deep within the substrate. GK PRO is a powerful biocidal detergent and it has a soapy/surfactant property that helps to wet the render thoroughly and the foam will dissolve grime when brushed. GK PRO is formulated for the eradication of algae and live contaminants. Other non-organic marks on render surfaces may need to be treated using different cleaning products/chemicals.

GK PRO contains no solvents, acids or bleach and will not affect silicone additives, sealants or coatings used in modern construction. GK PRO is for use on all thin coat and through colour render and EWI systems such as K-REND, Wetherby, SAS, Knauf, Weber and Parex.

The use of harsh, bleach based chemicals is quite common within the façade cleaning industry, and while these offer a 'quick fix' they have the potential to not only damage and discolour your façade,  but they can also have a negative impact on the health of local residents who may have respiratory issues such as asthma or COPD.

Our products pose no environmental risk and are biodegradable.