DelAgua OXFAM-DELAGUA, Руководство пользователя

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OXFAM-DELAGUA Water Testing Kit — Users Manual
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Appendix E
Alternative sources of water for media preparation
We would strongly recommend that you try to find a source of distilled water to
prepare the medium. However, we appreciate that this may not always be possible
and would suggest the following as suitable alternatives:
•
A high quality bottled water that has not been treated with chlorine or any
other disinfectant that has a residual activity.
•
Rainwater. Collect a sufficient volume of rainwater in a clean container and
leave it to stand overnight to allow any suspended matter to settle out.
Carefully pour off the water into a separate clean container. Alternatively, the
rainwater can be clarified by filtration through a membrane filter or, more
quickly, through one of the membrane pads (see the relevant paragraphs of
Section 5.4.4).
•
Water from a well protected groundwater source. Groundwater from a well
protected source is usually suitable for preparing the medium. However, check
the pH of the water before use to be sure that it is not too acidic or alkaline
(see Section 3.2).