Thanks EMP, this is something new to me.
From reading in the SODIS links you supplied it seems they suggest getting the water above 50°C to deal any amoebic dysentery (if present).
It says SODIS will kill ameoba.
Getting the temperature simply speeds up the process, but isnt required for disinfection.
http://www.thewaterschool.org/faq.html7. Is temperature important?
Short Answer
Yes and no. SODIS works much faster at temperatures above 45°C, but in most circumstances the water does not get this hot.
Full Answer
SODIS has been found to work faster above 45°C, and even three times as fast when the water exceeds 50°C (Berney et al). However, it is rare for ambient temperatures to get this high, and because SODIS bottles do not absorb much infrared radiation (which is the form of light that causes an increase in temperature) the water does not usually reach this threshold. For these reasons it is uncommon for this temperature factor to play a role in actual SODIS treatment.
The Water School has done a number of tests in Kisoro, Uganda, which is a mountainous area. In all of these tests the water temperature never approached 50°C, yet 100% kill of E. coli (the standard test organism) was observed. The highest temperature was 43°C and in most cases it was in the low 30's. The important thing is that SODIS is effective at the temperatures we experience in this area. It can be even more effective at higher temperatures, but does not impact our current projects.
Some have recommended SODIS bottles should be painted black on one side to increase the heat absorption from sunlight. Our experience does not support this recommendation. It adds another step and detracts from sustainability. This issue is addressed more fully in Q&A 10.
References
Berney et al., Efficacy of solar disinfection of Escherichia coli, Shigella Flexner, Salmonella Typhimurium and Vibrio cholera. J Appl Microbiol. (2006).
Try this manual, its simpler, although it doesnt include the oxygenation tip (fill 3/4 full, shake 20 seconds, fill full)
http://www.thewaterschool.org/pdf/sodis_training-english.pdfI assume amoebas would generally be present if there was fecal contamination, or am I wrong about that?
Probably. Its like giardia or cryptosporidium, its present everywhere, but poop doesn't guarantee presence, and eliminating eColi doesnt guarantee giardia/crypto is eliminated. In other words, don't let tests give you false confidence, don't take shortcuts with SODIS.
Some organisms such as Enteroviruses, Cryptosporidium,
Giardia and Amoebae however are more resistant than E.coli.
The absence of E.coli therefore does not necessarily indicate
their removal. Spores of sul?te-reducing Clostridia can be
used as an indicator for these organisms [11]. But such
analytical methods cannot be used for routine tests under
?eld conditions as they are time-consuming and expensive.
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