Physan 20 For Algae Control On Walkways:
PHYSAN 20 is effective at controlling algae on bricks, cement, walkways, walls, statuary, stucco, and other hardscape surfaces.
PHYSAN 20 will retard algae growth for a 10-14 day period after it is applied. Reapplication every 10-14 days is recommended to prevent algae recurrence.
Mixing and application directions:
USE: 1 Tablespoon PHYSAN 20 in one gallon of water. For heavy infestation, spray or swab. Let stand for one hour or more. Brush and wash away dead algae. Soak area again with PHYSAN 20 solution. Do not rinse. This product will inhibit the growth of algae on walkways. Allow to dry on surface, and repeat whenever algae growth returns.
NOTE: PHYSAN 20 can be used to retard and prevent algae growth on soil in the presence of plants and turf. However, the dilution rates for these applications are different (and smaller) than for algae control on hard surfaces. For these rates see SEEDS/SEEDLINGS/CUT FLOWER instructions