Cooling Water Bio Control

Cooling towers are constantly exposed to environmental contaminants and bacteria. This requires a rapid response, accurate detection and a tailored program to control biological growth. Nalco Water offers a complete line of oxidizing and non-oxidizing biocides, algaecides and biodispersants that are effective in a variety of cooling water applications, including open recirculating cooling towers, once-through cooling systems, closed loop cooling systems, air washers, cooling ponds, thermal energy storage tanks and pasteurizers.
Nalco Water Oxidant Controller is an accurate, reliable and robust oxidant measurement and control system for cooling water and process-critical applications. 


Rapid Bio Intelligence

Total Aerobic Bacteria Test

Staying ahead of surface bacteria in your water just got faster and easier with the Rapid Bio Intelligence total aerobic bacteria test for cooling water.


Oxidizing Biocides

Oxidizers are effective against all types of microorganisms in cooling systems, including bacteria, fungi, algae, and yeast. Our STA-BR-EX™, ControlBrom™, ACTIBROM™ and Purate™ products can effectively reduce the amount of oxidizing biocide required to control microbiological activity in cooling water. 

Non-oxidizing Biocides
Unlike oxidizers, non-oxidizers are more effective when applied in slug doses to target specific organisms. It’s best practice to use a non-oxidizer in conjunction with an oxidizer to maintain control of cooling water systems. We offer an array of compounds to ensure the right treatment for your cooling system.

Macrofouling Control

For control of macrofouling by zebra mussels and other mollusks, we offer effective molluscicide treatments that can be used in fresh and potable water systems. Your sales engineer can help choose the right treatment program for your system.


Algae can be more difficult to control on a common biocide treatment plan. Nalco Water offers products to beat algae in cooling systems and ponds including potable water.

Biodispersants should be used as part of a complete biocontrol program. They will break up biofilms and suspend bacteria so they are more readily killed by biocides.

Water Safety

Environmental Hygiene Services provides specialized services to help control private and public health risks due to pathogens such as Legionella. They conduct detailed risk assessments and offer ongoing management programs customized for your specific environment.