Expanses of water devoted to fish cultivation

In fish cultivation waters, which must generally be light and clear because the majority of fish species would otherwise migrate, the oxygen content 

Domestic waste water Industrial waste water 

Waste water from critical locations, e.g. hospitals, chemical factories producing toxic materials, metal foundries and galvanization plants, etc. 

Waste water with inflammable organic solvents, oils and greases, phenols or chlorine compounds 

Seepage water from solid waste (rubbish dumps, etc.) 

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