Algae

Signs of Damage & What Algae Does to Water Systems

Algae can cause multiple issues across irrigation systems, water bodies and turf facilities. You may be dealing with algae if you notice:

• Clogged pumps, irrigation lines and aerators

• Sprinkler nozzles blocked by fine unicellular algae

• Build-up of organic material in and around water fixtures

• Reduced water pressure or irrigation downtime due to blockages

• Increased suspended solids in the water, causing a murky appearance

• Pesticides (e.g. glyphosate) becoming less effective because algal cells bind to chemical molecules

• Poor-quality water reaching turf surfaces, leaving residue or reducing uniformity of spray coverage

• Deoxygenation of the water due to algal photosynthesis and respiration

• Fish kills often the earliest visible sign of severe oxygen depletion

• Anaerobic conditions leading to foul odours and toxic by-products

• Production of dangerous toxins (especially from blue/green algae), posing risks to humans, livestock and wildlife

If left unmanaged, algae can escalate quickly, impacting turf, irrigation performance, dam health and overall water safety.

How to Control Algae

Managing algae involves treating the current bloom and preventing future outbreaks. When algae are active, algaecides are often needed. Traditional copper sulphate can work, but it becomes inactive quickly in hard water, can stain dam edges, and may harm aquatic plants and animals.

A better option is complexed or chelated copper algaecides, which stay active longer, work at lower rates and avoid staining. These products deliver copper in a stable form, making them more reliable and safer for the environment.

Long-term control depends on managing nutrients in the water. Algae thrive on nitrogen and phosphorus, so regular water testing and reducing fertiliser runoff are essential. After treatment, dead algae release nutrients back into the water, which can trigger new blooms. Using nutrient-binding products helps prevent this cycle.

Ongoing monitoring checking nutrient levels, improving water movement and watching for early signs of regrowth is key to maintaining clear, healthy water.

Common Questions About Algae (FAQs)

• Why does algae keep coming back? High nutrient levels (N & P), warm weather and stagnant water all encourage repeated blooms.

• Can algae affect pesticide performance? Yes. Suspended algae bind to many pesticide molecules especially glyphosate reducing their effectiveness.

• Is blue/green algae dangerous? Yes. Cyanobacteria can produce toxins harmful to people, livestock, pets and wildlife. Identification and prompt action are essential.

• Can algae damage irrigation systems? Both filamentous and unicellular algae can clog pumps, block nozzles and disrupt sprinkler output.

• What is the safest long-term control method? A combination of nutrient management, regular monitoring, and using complexed copper algaecides when required.