Unusual levels of dissolved oxygen - See photos ...Sensor was covered with algae.
See photos below
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Cylindrotheca closterium - Fhoto: dr. Janja France | Pleurosigma - Fhoto: dr. Janja France |
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Navicula - Fhoto: dr. Janja France | Nitzschia longissima - Fhoto: dr. Janja France |
Prepared by: Janez Forte