Non-Oxidizing Biocide

Is microbial growth fouling your system? If left unchecked, microbial contamination can reduce heat transfer efficiency, cause corrosion and create potential health and safety issues.

AQUAGUARD 651 is a fast acting, effective broad spectrum biocide that can be used at low levels to control algae and bacteria including sulphate reducing bacteria (SRB).

AQUAGUARD 651 is also particularly effective for control of pseudomonas aeruginosa and legionella, common microbial contaminants in cooling and humidification systems.

In oilfield applications, AQUAGUARD 651 has been proven to be effective at controlling both acid producing bacteria (APB) and sulphate reducing bacteria (SRB) and their bacterial slimes. For oilfield applications an alternative winterized formulation is also available—AQUAGUARD 651W.


  • Effective, broad spectrum antimicrobial agent (biocide)
  • Economical, low dosages required to kill and inhibit a wide variety of microbial contaminants
  • Non-oxidizing and formaldehyde free
  • Non-foaming
  • Most effective at neutral and acidic pH ranges
  • Readily biodegradable when diluted to less than minimum inhibitory concentration (MIC)
  • Also available in a winterized formulation—AQUAGUARD 651W


AQUAGUARD 651 is registered for use with the Pest Management Regulatory Agency (PMRA) for use in heat exchangers, cooling towers, condensers and air washers as well as in oilfield applications.

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