Makes it easy to monitor the copper level in fresh and marine water. Copper (Cu) is very toxic especially for invertebrates such as shrimps and crustaceans, but fish also react very sensitively to elevated copper levels. There are many possible causes for copper enrichment, including medical or algae combating treatments. The sera Cu-Test allows checking quickly whether fish or invertebrates are safe. sera aquatan provides help in case of elevated copper levels. Sufficient for approx. 50 measurements.