algae on tarmac

henryj

does anyone know how to remove algae from tarmac without harming animals

Sledge_2

A pressure washer is good, don't need to use any chemicals, just the water pressure alone gets anything off.

Cardew

I have tried everything to no avail.

A pressure washer obviously works, but lifts a little of the tarmac each time; although I suppose it depends on the density of the darmac.

Plenty of chemicals kill the algae, but the dead algae is still difficult to get off. Leaving the dead algae just provides nutrients for the new algae the forms.

I have now given up and eventually the old stuff dies and becomes loose, but the new plants are underneath.

jancee_2

Scatter washing soda liberally and sprinkle with water. Use a stiff yard brush next day.