Fish test for sewage

When investigating the toxic effect of sewage on organisms, it is always 

One of the problems of ecotoxicology is deciding whether an observed change is ecologically significant. Past experience shows that biotic systems have the ability to adapt to changed conditions and to regenerate to a certain 

In general fish tests can be conducted in three different ways  

In the Federal Republic of Germany a test is performed in accordance with DIN 38412, Part 20, using the golden orfe (Leuciscus idus), but it has not 

The following description is of the test used in the Federal Republic of Germany with the golden orfe. 

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