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Pond skimmer

I have a garden pond that suffers from "pea-soup" algae. A thunderstorm recently flooded...

19 August 2015

I have a garden pond that suffers from “pea-soup” algae. A thunderstorm recently flooded the nearby road, overflowing into my garden and the pond. The next morning the algae had gone. What was in the floodwater that managed to clear the algae?

Colin Carter, Marlborough, Wiltshire, UK

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