Algae on walls is one of those problems that starts small and then quietly spreads. A pale green film after the rains can turn into stubborn stains, patchy discolouration, and a wall paint that never looks truly clean. 

Over time, persistent dampness can soften plaster, weaken paint grip, and encourage other microbial growth. In many Indian cities, the combination of monsoon moisture, warm air, and shaded areas creates ideal conditions for algae growth on walls.