Drinking Water from watertanks

[redneckrob]

Originally Posted by GordMay

The main protozoa of concern, in North America, are Giardia and Cryptosporidium. They may be found in water, following direct or indirect contamination by the faeces of humans or other animals. They can survive for long periods of time, in the environment, and are highly resistant to chlorine-based disinfection.
Many but not all available home water filters remove Cryptosporidium. The absolute 1 micron filter will more consistently remove Cryptosporidium, than a nominal 1 micron filter. Some nominal 1 micron filters will allow 20% to 30% of 1 micron particles (like Cryptosporidium) to pass through.
Filter manufacturers may pay to have their filters tested, to see if they remove Cryptosporidium or Giardia. To find out if a particular filter is certified to remove Cryptosporidium, you can look for “NSF 53” or “NSF 58”, plus the words “cyst reduction” or “cyst removal” on the product label information.
Because filter testing is expensive and voluntary, some filters that may work against Cryptosporidium may not have been tested. If you chose to use a product not labeled “NSF 53” or “NSF 58”, select those technologies more likely to reduce Cryptosporidium, including filters with reverse osmosis, and those that have an Absolute (NOT Nominal) pore size of 1 micron or smaller (Microfiltration or Ultrfiltration).

Just to clarify, if it is either NSF 53 or NSF 58 and has one of the cyst labels is it going to be absolute 1 micron, or does it also need to also specifically say something about absolute 1 micron for us to know that it meets that standard? I'm sure it's something I could look up but it sounds like you've already done the heavy lifting of researching this. I had Giardia in high school (home well water contaminated by cows) and don't want to ever have it again!

[coopec43]

Originally Posted by sailorchic34

Here I am 15 years drinking unfiltered water from the water tank. Myself having helped design several biopharmaceutical plants, I realize that the filter media used in water filters happen to be a perfect growth media for bacteria.

That's the main reason I don't put a filter on my water tank. Well other than the fact that we have a millions of years of evolution, where we did nothing but drink water out of streams or well's.

How many of us died of cholera, hepatitis, gastroenteritis..... by drinking contaminated water!!

[GordMay]

Originally Posted by redneckrob

... does it also need to also specifically say something about absolute 1 micron for us to know that it meets that standard? ...

Filters tested to remove Cryptosporidium will display any of the four messages below:
- Reverse osmosis (with or without NSF 53 or NSF 58 labeling)
- Absolute pore size of 1 micron or smaller (with or without NSF 53 or NSF 58 labeling)
- Tested and certified to NSF/ANSI Standard 53 or NSF/ANSI Standard 58 for cyst removal
- Tested and certified to NSF/ANSI Standard 53 or NSF/ANSI Standard 58 for cyst reduction

Here I am 15 years drinking unfiltered water from the water tank. Myself having helped design several biopharmaceutical plants, I realize that the filter media used in water filters happen to be a perfect growth media for bacteria...

Filters do collect germs from water, so someone who is not immunocompromised should change the filter cartridges. Anyone changing the cartridges should wear gloves and wash hands afterwards. Filters may not remove Cryptosporidium as well as boiling does, because even good brands of filters may sometimes have manufacturing flaws that allow small numbers of Cryptosporidium to get in past the filter. Selection of certified filters provides additional assurance against such flaws. Also, poor filter maintenance or failure to replace the filter cartridges as recommended by the manufacturer can cause a filter to fail.

[Discovery 3]

Originally Posted by sailorchic34

Here I am 15 years drinking unfiltered water from the water tank. Myself having helped design several biopharmaceutical plants, I realize that the filter media used in water filters happen to be a perfect growth media for bacteria.

That's the main reason I don't put a filter on my water tank. Well other than the fact that we have a millions of years of evolution, where we did nothing but drink water out of streams or well's.

I dare say that the filter should be changed out or serviced at regular intervals to avoid growing a humuncolous in the bilge,lol.

[tobo]

By accident I saw a video of a catamaran crew sailing in the Caribbean and using a UV-LED system called "acuva" of a company www.acuvatech.com. Anybody having experiences with this system? It's quite expensive but should be excellent.

[IronicIslander]

Yes, We have an Acuva LED system for our off-grid island cabin and are totally happy with its performance. Very well engineered and designed, very low power draw and zero maintenance. Several of our neighbours also have them. A real game changer it auto runs on instantly when flow sensed and shuts off after so very little draw.

[Puddleduck]

Originally Posted by IronicIslander

Yes, We have an Acuva LED system for our off-grid island cabin and are totally happy with its performance. Very well engineered and designed, very low power draw and zero maintenance. Several of our neighbours also have them. A real game changer it auto runs on instantly when flow sensed and shuts off after so very little draw.

Interesting. LEDs have historically been rubbish at kicking out light wavelengths in the UV spectrum. They generally require a lot of ‘power’ to generate uv light which by default makes them power hungry to be usefully for sterilisation.

Unless the technology has improved, the greater the wattage the better the sterilisation (relative to contact time (flow rate)).

[IronicIslander]

Regarding Acuva LED UV Treatment - Yes, new technology. The University of British Columbia Physics Department (my Alma Mater) created the spinoff company Acuva Technologies Inc. which sells the units which incorporate 250-280 nm UV LED treatment that exceeds either NSF Class A (40mJ/cm² UV dose) or B treatment standards (16mJ/cm² UV dose) depending on flow rate and model. Worth looking into for utter simplicity and zero maintenance.

[surf_km55]

Let's thank the Internet for a random & completely
unrelated comment to the subject discussion that ended almost a year and a half ago.... that wreaks of a product plug. I want the minute I spent on this back.

[Captmatt]

Yes this is an oldy!

[coopec43]

Disadvantages of water dispensers:

• Although perceived as safe, try to keep it away from dust. They can easily become a breeding ground for diseases.
• Cost. The water dispenser itself does not cost much, but it requires a new filter after so many uses. This extra expense increases especially during the summer and can add up.
• Check the quality of the plastic before you make the purchase. If it is made of harmful cheap plastic material, the purpose of drinking chemical free water is pointless. Read our article on: BPA Free Water Bottles
• If you refill old water bottles, you might be causing more harm than good. Most water bottles are meant to only be used once

https://filtercon.wordpress.com/2013...er-dispensers/

[tallship]

Originally Posted by tobo

As we get our new Hanse 508 by the end of this year we are thinking of the use of the water tanks for drinking purposes as we are really tired of hauling aboard these masses of PET bottles every week. Reading an article in the German Yacht recently I was impressed by the UV-system "Double Blue" of Instant Trust Marine (InstantTrust Marine - Always clean drinking water on board) . Does anybody have experiences in this field?

One of the best investments I ever made was replacing a defective watermaker. For day and weekend excursions we would cart water that we brought aboard, after it started failing, but then issues surrounding conservation emerged with respect to cooking and showering.

At first, I was going to replace the watermaker with a like (similar, it had been discontinued) model, but at the last minute I spoke to the good folks over at the [bold]Watermaker Store[/bold] in Sandy Eggo, and they provided me with a quick education that has served me well ever since.

You may or may not need or desire to go the route of a watermaker, but personally, as you have what seems to be a solution for your particular situation at this juncture, but here's what I learned years ago, in the hopes that it may benefit you at some point in the future, and it has saved me from a lot of heartache and strife.

You calculate your daily needs on average, so this is what you aim to bring aboard, purify, or make via R.O. on a daily basis, but with respect to the latter solution, this is wrong thinking. The amount of battery stress or duty cycle involved with running a water maker constantly when budgeting for a daily production of your needs adds additional wear and decreases the life of some systems aboard your vessel, instead, target 1 (2 max) hours as the amount of time your watermaker needs to actually run to produce the amount of potable water you wish to replenish every day, if you have leftover reserves then you simply don't need to run it the next day, but this will save on wear and tear and your batteries as well as your watermaker will last longer.

I hope that helps

[Mike OReilly]

Originally Posted by Paul Kelly

How much bleach do you add Mike? It'd be very helpful to know. Thanks.

Hi Paul. We more-or-less follow Peggy Hall's recommendation: ~1 quart bleach/50 gal water tank capacity

We let it sit for 6 to 12 hrs.


Opps... I see Paul's question was some time ago. Sorry I missed it earlier.

[Cheechako]

Originally Posted by Mike OReilly

Hi Paul. We more-or-less follow Peggy Hall's recommendation: ~1 quart bleach/50 gal water tank capacity

We let it sit for 6 to 12 hrs.


Opps... I see Paul's question was some time ago. Sorry I missed it earlier.

Whoa! Are you sure you've got that right? That's a ton of bleach. At home I use 1-2 cup of bleach per 500 gallon tank.

[rslifkin]

In general, for sanitizing the system, the more bleach you use, the less contact time is needed before flushing it out. For just providing a chlorine residual and making sure the water stays good it doesn't take much bleach at all though.