Hi Jan,

I don't disagree that the algae uses the nitrate, that's what
plant life does, but it could be a problem if a UV unit is used to
clear the water and the dead algae isn't removed.

Nitrate and phosphates can be problem in the water here in the UK and I
thought they would be in any modern agricultural society due to runoff
from the fields. Phosphate is also added here as a lubricant for the
pumps and valves.

Patrick mentioned nitrites in one post I think, that should be zero
just the same as ammonia.

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Regards - Rodney Pont
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