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Technical Help
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3D TRASAR
5500 - Installation & Operation Manual
14. Does 3D TRASAR Bio-Control control algae growth?
3D TRASAR Bio-Control has not been designed to specifically control algae.
Even though the bio-reporter reacts with and responds to algae, the microbial activity attributable to
algae growth usually represents only a fraction of the total system microbial activity. For this
reason, 3D TRASAR Bio-Control may not apply oxidizing biocide specifically in response to, or at a
dosage sufficient to control, algae growth.
3D TRASAR Bio-Control does not maintain high residuals of halogen in a tower. If algae is a known
problem and over-halogenation has been the historical method of algal control, it is crucial that an
algaecide be routinely used in conjunction with the oxidizing biocide under bio-reporter control.
If algaecide use is not feasible, another option is to use regular scheduled oxidizing biocide slugs
overlaid on 3D TRASAR Bio-Control.
3D TRASAR Bio-Shock mode, the all slug mode of oxidizing biocide application with bio-reporter
control may be also used in systems where algae is a problem
Algae grows in semi-wetted areas exposed to light. Chlorine and bromine are not particularly
effective under these conditions. Using these halogens at high levels in the recirculating water
results in a vapor pressure of halogen in the tower decks resulting in algae kill. Since 3D TRASAR
Bio-Control only maintains very small TRH levels in the water, algae control by this mechanism is
not active.
We recommend covering exposed tower decks.
15. What key issues I should be aware of before I decide to use 3D TRASAR Bio-
Control?
•
3D TRASAR Bio-Control should be used in conjunction with an appropriate oxidizing
biocide, a non-oxidizer and a bio-dispersant
. Additionally, if presence of algae has been a
problem in the past and was handled through high TRH levels in the tower, an algaecide such as
N-90005 must be used.
• 3D TRASAR Bio-Control will impart a slight blue color to the tower water. The effect will be ampli-
fied as the depth of the water in the basin is increased. This is normal.
• 3D TRASAR Bio-Control may or may not reduce the oxidant usage in the system. It depends
upon whether the system was in good control or not before 3D TRASAR Bio-Control.
• 3D TRASAR Bio-Control is not the same as maintaining a fixed halogen residual. The measured
TRH levels depend upon the system microbiological activity and demand. In fact, measured TRH
levels may be zero during a significant portion.