Wet or “charged” systems feature pipes that carry rainwater underground to your tank. The water remains in your pipes between rain events and can become stagnant.
Anaerobic fermentation occurs when leaves or other organic matter breaks down in these water-filled pipes. It produces sulphides that can make your water cloudy, smelly and discoloured. This fouled water then goes through to your tank when it rains.
Organic and inorganic sediments rest on the bottom of your rainwater tank.
They can include harmful particles including heavy metals. When this sediment is stirred by water flow it can resuspend in your tank water, becoming hazardous to your health and increasing the loading on your pumps and treatment systems.
Algae is a photosynthetic organism that thrives in sunlight and contaminates water. Sunlight creates an environment for algae as it enters your tank through openings and inlets.