Catchment Hot Water Temps

[Punaperson]

Answering Chas: First one was a Paloma, the one I have now is a Bosch. (I would have bought a Paloma again, but no one had one is stock when I needed it, and it would have taken a few weeks before it came in.)

[Carey]

Voyager, for RLW, you would need a filter below 1 micron (the RLW group has recently published that they can be present at 1 micron, have not published studies below that level)

Nematodes (RLW) and other things like bacteria, mold spore & such do not like Ozone, & you can get inline ozonation water purification systems, but most are energy users (figure on a whole house system that can purify 5.6gal/min will have an Electrical Consumption about: 0.5 Amp, 60 Watts; 3.5 gal/min EC ~ 0.26 Amp, 32 Watts) plus is no residuals in the water...

[My 2 cents]

"Blues has the correct idea"

I was considering a similar system but with a with an on-demand heater with a temperature regulator. They are supposed to put out the correct temp regardless of the input water temp, so I was hoping it would simply kick on whenever the input temp dropped below the output setting and and remain off if the input temp was equal to or higher than the output setting. Seems like it would be the perfect system if it worked. Has anyone tried this or have any experience with it?

[Midnight Rambler]

Carey: in the paper they found that RLW did not pass through a 5 micron carbon block filter. The ones that got through the 10 micron and smaller polypro filters were after letting them sit for a while before running water through again, suggesting that the worms are able to make their way through faults in the polypro filters when given enough time, but not the carbon ones. RLW are about 25 microns wide so they should not be able to get through at least a 10 micron filter, though the nominal ratings aren't precise; for example, the 20 micron filter says it removes 95% of particles over 20 microns and 99% over 30 microns.

[Chas]

Thanks Punaperson, I’ll check them out. Sorry for the hijack 1v1.

[Carey]

"These studies substantiate the epidemiological significance of contaminated water as a source of
A. cantonensis transmission. We have clearly demonstrated the potential for shedding of the
infective stage larvae in water from drowned P. martensi, a highly efficient, intermediate host,
recently introduced to Hawai`i. In contrast to previous studies, our results demonstrate that
undamaged P. martensi are capable of shedding several hundred infective stage larvae that can
survive in water for several weeks. While current rainwater catchment guidelines state that a 20
um sediment filter should be sufficient to block the infective stage larvae, our findings show that
live, infective-stage larvae were able to traverse 20, 10, 5, and 1um commercially available
wound or spun polypropylene sediment filters."
bioRxiv preprint first posted online Dec. 13, 2018; doi: http://dx.doi.org/10.1101/496273. The copyright holder for this preprint (which was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY 4.0 International license.

[MarkP]

The same study concluded that the 5um carbon block filters stopped the larvae. That's an equally valid result. To those of us who read the report and discussed it over on the thread about rat lungworm, this omission is conspicuous.

It is important in all this to understand the limitations in any technology. The idea that a filter labeled 10um may have many 50um holes in it may seem wrong but the rating system allows for it and if you are only concerned with stopping sediment like pollen drifting in on the wind then 10um being an average still does the job. The average consumer didn't have to concern themselves before about the difference between nominal and absolute ratings.

[Carey]

MidRambler, I was responding to your leaving off the carbon block reference in YOUR response:
"RLW are about 25 microns wide so they should not be able to get through at least a 10 micron filter, though the nominal ratings aren't precise; for example, the 20 micron filter says it removes 95% of particles over 20 microns and 99% over 30 microns."
As to the study, it was very much an initial trial, as you have read, there were inconsistencies in larval availability, run time for the filter trials & other things that happen on initial trials, HOWEVER, the fact that they can "weasel" through inconsistent pukas would give rise to recommend care in trusting filtration alone for RLW control...

[Punaperson]

To 1Voyager!, if you have time to answer: what made you and your spouse so dislike the on-demand water heater in the house you were renting? Having had a very good experience with mine over many years, and having read so many of your posts that are right on the mark, I'm just curious.

[ElysianWort]

Hi 1V1 my opinion is that your problem has nothing to do with your water. Heated or otherwise. As you suspected it's just a variety of fungus that will try to live on your skin if you let it. Comes out more often in hot weather when we sweat.
In Hawaii there seems to be a type of fungus or mold for every surface including ourselves.

http://www.punaweb.org/Forum/topic.asp?TOPIC_ID=20725&SearchTerms=puna,people,skin,fungus