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The following Technical Information Bulletin is a re-write of a Bio-Lab US document released during the mid- 1990's.

Introducing Algizine

BioGuard Algizine is an algaecide designed to effectively destroy and prevent various strains of black and green algae in swimming pool water. It has two active ingredients:

1. 320g/L poly[oxyethylene(dimethylimino)ethylene(dimethylimino)ethylene dichloride].

2. 54 g/L 6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine, otherwise simply known as Simazine.


Algizine is neither an oxidising algaecide nor a heavy metal-based algaecide. It is the combination of a cationic, polymeric quaternary ammonium compound (1) and a herbicide registered for use in swimming pools (2). The quaternary ammonium compound in Algizine attacks algae by coating their surfaces and breaking down the mechanism that controls diffusion through the permeable membrane. This can have the effect of ceasing cell functions and allowing the second active ingredient into the cell. The Simazine, once within the algae plant membrane, serves to disrupt the process of photosynthesis by blocking the fixation of carbon dioxide. The synergistic action of both active ingredients is an important feature of Algizine.


Algizine is optimally effective against black algae and most types of green algae. It is also reasonably compatible with chlorine. However, as part of Algizine is an organic compound, it will slowly break down over time in the presence of normal levels of chlorine. More rapid degradation will be experienced during oxidation applications. A weekly addition is recommended for preventative maintenance. Algizine is effective in the normal pH ranges found in swimming pools (7.2 – 7.8). The product itself does not affect pH.


If the destruction of Algizine is desired after the algae is killed off, apply Super Chlor 35 according to the label directions and wait for the chlorine residual to drop. This will then allow backwashing or watering onto lawns, gardens, etc.


Algizine is compatible with all BioGuard Pool Chemicals and is non-foaming, non-staining and non-corrosive to pool equipment.



  • Before adding Algizine, balance the pool water pH to 7.4 – 7.6 and brush the algae growth from the walls and floor of the pool.
  • Vacuum any visible algae to waste.
  • Shake Algizine well before mixing. Mix the correct dosage of Algizine in a bucket of water and apply the slurry evenly around the edges of the pool with the filter running.
  • Do not add directly after an oxidation treatment. Add with chlorine residual at normal levels.
  • Swimming may be resumed once the algae growth is destroyed and the water clarity restored.


Precaution: Do not use treated water on plants or lawns and do not contaminate water supplies, lakes, streams, ponds or irrigational waters. Algizine is considered to be relatively non-toxic to fish and wildlife, but should not be used in fish tanks if the fish is for human consumption.


The above information is supplied by Bio-Lab and represents its best interpretation of available technical information at the time of preparation. The sole purpose is to supply factual information to Bio-Lab customers. It is not to be taken out of context nor used as support for any other claim not made herein.