DelAgua OXFAM-DELAGUA, User Manual

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OXFAM-DELAGUA Water Testing Kit — Users Manual
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6.
Keep the filtration apparatus sealed for at least 15 minutes before use.
Note: It is best to sterilise the filtration apparatus immediately after each analysis
and to keep the filtration apparatus in a sterile condition during transport and
storage. In this way, the filtration apparatus is always ready for use.
3.2 Preparation of Culture Medium in the Laboratory
You will need the following items:
1.
38.1g of Membrane Lauryl Sulphate Broth (MLSB)(a)
2. Distilled water (b). Check that the pH of the water is between 7.0 and
7.8 using the comparator and phenol red tablets (Section 5.2)
3. Ten polypropylene bottles (60ml)
4. Measuring cylinder or graduated flask
5. Clean flask or beaker, approximately 1 litre capacity
6. Pressure cooker, steriliser or autoclave(c)
7. Heating element, stove or burner
(a) The medium is available in 38.1g, pre-weighed amounts from Delagua
Water Testing Ltd
(b) See Appendix E for suggested alternative sources of water
(c) A portable steriliser kit is available from Delagua Water Testing Ltd
Method
1.
Carefully wash the plastic polypropylene bottles in clean, warm water before
use. If necessary, use a little detergent and then rinse well with clean water to
remove all traces of the detergent.
2. Measure out 500ml of distilled water using the measuring cylinder or
graduated flask. Decant approximately half of the water into the clean flask or
beaker.