How To Remove Algae From A Cooling Tower

Algae growth is one of the most common and damaging problems in a water cooling tower. If not properly controlled, algae can clog distribution systems, reduce heat transfer efficiency, increase corrosion risk, and raise operating costs. Whether you operate an open water cooled tower or a closed loop cooling tower, effective algae removal and prevention are critical to maintaining a reliable water cooling tower system.

This article provides a complete guide on how to remove algae from a cooling tower, covering causes, removal methods, chemical and mechanical treatment, and long-term prevention strategies. The recommendations reflect industry best practices and the engineering experience of MACH Cooling (https://www.machcooling.com/), a professional manufacturer of high-performance cooling towers.

 What Causes Algae Growth in Cooling Towers

Algae thrive in warm, nutrient-rich, and sunlit environments—conditions commonly found in cooling towers.

 Key Conditions That Promote Algae

• Warm circulating water

• Direct sunlight exposure

• Poor cooling tower water supply quality

• Inadequate water treatment

• Low circulation or stagnant zones

Once algae form, they spread quickly across basins, fill media, and piping surfaces.

 Why Algae Must Be Removed Quickly

Unchecked algae growth negatively affects the entire water cooling tower system.

Operational Problems Caused by Algae

• Reduced heat transfer efficiency

• Blocked spray nozzles and strainers

• Increased pump energy consumption

• Accelerated corrosion under deposits

 Health and Safety Risks

Algae can provide a breeding environment for harmful bacteria, increasing biological risk and compliance concerns.

 How to Remove Algae from a Cooling Tower

Step-by-Step Algae Removal Process

 Step 1 – Isolate and Inspect the Cooling Tower

• Shut down the water cooled tower if possible

• Inspect basin, fill, drift eliminators, and piping

• Identify areas of heavy algae accumulation

Step 2 – Mechanical Cleaning

Mechanical removal is the first and most important step.

• Drain the cooling tower basin

• Manually scrape algae from surfaces

• Use high-pressure water cleaning where appropriate

• Clean strainers and spray nozzles

Mechanical cleaning removes bulk algae and improves chemical treatment effectiveness.

Step 3 – Chemical Algaecide Treatment

After physical cleaning, chemical treatment is required to eliminate remaining algae.

Common treatments include:

• Oxidizing biocides (chlorine, bromine)

• Non-oxidizing algaecides

• Shock dosing for severe infestations

Chemical dosing must be carefully controlled to protect system materials and maintain stable operation.

 Step 4 – System Flushing and Restart

• Flush the system to remove dead algae

• Restore proper cooling tower water supply

• Restart circulation and monitor water quality

 Algae Control in Closed Loop Cooling Towers

A closed loop cooling tower has lower algae risk because process fluid is isolated from air. However, algae can still develop in the external spray water circuit.

 Best Practices for Closed Loop Systems

• Maintain clean spray water

• Monitor heat exchanger surfaces

• Use controlled biocide programs

• Prevent debris accumulation

Proper maintenance ensures stable performance and long equipment life.

Preventing Algae Growth Long Term

 Improve Water Quality Management

Consistent water treatment is essential for algae prevention.

Key actions:

• Maintain proper biocide residuals

• Control nutrients and dissolved solids

• Monitor pH and conductivity

Routine testing keeps algae under control before it becomes visible.

 Reduce Sunlight Exposure

Sunlight accelerates algae growth.

Solutions include:

• Installing tower louvers

• Using opaque or covered basins

• Optimizing tower layout and orientation

 Maintain Proper Circulation and Flow

Low flow and stagnant zones allow algae to settle and grow.

• Ensure even water distribution

• Avoid dead zones in basins

• Keep pumps and spray systems operating correctly

Cooling Tower Algae Removal and Prevention Table

Common Algae Removal Methods

Algae Prevention Best Practices

MACH Cooling – Reliable Cooling Tower Solutions

MACH Cooling (https://www.machcooling.com/) designs and manufactures high-efficiency water cooling towers, water cooled towers, and closed loop cooling towers with a strong focus on maintainability and water quality control.

 MACH Cooling Advantages

• Optimized water distribution design

• Easy-access basins for cleaning

• Materials resistant to fouling and corrosion

• Engineering support for water treatment and maintenance

MACH Cooling systems help minimize algae formation while ensuring reliable thermal performance.

Conclusion

Algae removal from a water cooling tower requires a systematic approach that combines mechanical cleaning, chemical treatment, and long-term prevention strategies. By maintaining proper water quality, ensuring consistent circulation, and reducing sunlight exposure, algae growth can be effectively controlled.

Whether operating an open water cooled tower or a closed loop cooling tower, proactive maintenance and professional system design are the keys to long-term success. For engineered cooling tower solutions and expert support, visit:

https://www.machcooling.com/

A clean cooling tower is not only more efficient—it is safer, more reliable, and more cost-effective over its entire service life.