Quality Control in Aquaculture Water Analyses

Water analysis required to verify the effectiveness of water quality management procedures is becoming an important aspect of aquaculture. Thus, many producers make analyses on site, and samples often are sent to commercial or institutional laboratories for special analyses. Recent assessments have revealed large errors in analytical results for samples sent to laboratories, and there no doubt are many opportunities for errors in analyses done on site. There appears to be a general lack of quality control to assure that precision and accuracy are being achieved. Moreover, there is considerable reliance - especially at aquaculture facilities - upon water test kits. Some types of kits can produce reliable results; others may be notoriously inaccurate. This presentation will provide methods for assessing the precision and accuracy of water analyses. Simple methods of quality control that can be used for tracking precision and accuracy of water analyses made at aquaculture facilities will be explained. In addition, methods for assessing the probable accuracy of samples sent to outside laboratories will be discussed.