Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 30-09-2012, 20:09   #1
Registered User
 
silverp40's Avatar

Join Date: Jan 2010
Location: Usually where the boat is...
Boat: Pearson 40
Posts: 514
Images: 7
TDS Water Quality Tester

Hi all

Does anyone have any experience with a total disolved solids tester?

Primarily used for testing water quality, I think it would be a good tester for on board filters as well as when getting water in places where water quality is suspect (like Mexico!).

Might also be useful for testing a watermaker output ...

Here is a small, portable one:

Thanks for any ideas!
Attached Images
 
__________________

__________________
silverp40 is offline   Reply With Quote
Old 30-09-2012, 21:18   #2
Registered User

Join Date: Dec 2009
Posts: 3,016
Images: 4
TDS has little to do with water-borne pathogens. Need a lab for that. The meter is for monitoring RO performance in removing *dissolved* minerals, principally salts, not solid living things or toxins.

Chlorination is helpful for the pathogens. Water in Mexico is generally pretty good in the cruising areas.
__________________

__________________
daddle is offline   Reply With Quote
Old 30-09-2012, 22:31   #3
Senior Cruiser
 
senormechanico's Avatar

Cruisers Forum Supporter

Join Date: Aug 2003
Boat: Dragonfly 1000 trimaran
Posts: 5,821
Re: TDS Water Quality Tester

There are lots of them on ebay.
Here's the one I use for my Spectra.
Works great, and cheap.

Digital LCD TDS Meter Tester Water Quality Filter Purity Pen Stick 0-9999 PPM | eBay
__________________
Memento,homo, quia pulvis es, et in pulverem reverteris.
senormechanico is offline   Reply With Quote
Old 01-10-2012, 16:58   #4
Registered User
 
silverp40's Avatar

Join Date: Jan 2010
Location: Usually where the boat is...
Boat: Pearson 40
Posts: 514
Images: 7
Re: TDS Water Quality Tester

Well, the TDs can also tell me if the water I obtain for the tanks has traces of heavy metals from old iron pipes, sediments, etc. Larger pathogens like girardia also read.

Also is good to know when to change the water filter for the drinking water...

Mr mechanico, do you calibrate yours? Do you have to buy a calibration kit/samples? Thanks for turning me on to this one - it is half the cost of the one in my pic....

PS Water in western Mexico, El Salvador, Guatemala is always suspect - maybe some fancier marinas have good filtration systems on their hoses....This has been going on there since the seventies at least in my experience (and sickness too).
__________________
silverp40 is offline   Reply With Quote
Old 01-10-2012, 17:26   #5
Registered User
 
S/V Illusion's Avatar

Join Date: Oct 2007
Location: Lakewood Ranch, FLORIDA
Boat: Alden 50, Sarasota, Florida
Posts: 1,692
Re: TDS Water Quality Tester

These things should be outlawed as they can be dangerous for giving nothing more than a false sense of security. This is the kind of marketing the door-to-door snake oil salesmen use trying to convince unsuspecting people to buy their water filter.

If you want to know your water quality, have it tested properly by a certified lab which would never use this thing as it would cause them to lose their certification.

TDS is not an indication of anything significant and I really wish people would stop and think about these magic dust toys with some common sense.
__________________
S/V Illusion is offline   Reply With Quote
Old 01-10-2012, 17:46   #6
Don't ask if you can't handle it
 
sailorboy1's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: On the boat somewhere
Boat: Hunter 410
Posts: 12,305
Re: TDS Water Quality Tester

I use one probably 50+ times a week for industrial water testing. But unless you are testing your RO water it isn't going to tell you anything on the boat (well maybe except for whether your leak is potable water or seawater). TDS varies a lot from place to place and doesn't mean anything as far as quality of the water for drinking.
__________________
jobless, houseless, clueless, living on a boat and cruising around somewhere
sailorboy1 is offline   Reply With Quote
Old 01-10-2012, 18:09   #7
Registered User
 
silverp40's Avatar

Join Date: Jan 2010
Location: Usually where the boat is...
Boat: Pearson 40
Posts: 514
Images: 7
Re: TDS Water Quality Tester

All right, can it tell me if my water filter works or needs changing?
__________________
silverp40 is offline   Reply With Quote
Old 01-10-2012, 18:39   #8
Registered User

Join Date: Dec 2010
Location: W Carib
Boat: Wildcat 35, Hobie 33
Posts: 7,908
Re: TDS Water Quality Tester

As others have posted, a TDS meter is useful for determining how effective your RO systems is operating, but tells you almost nothing about general water quality.
__________________
belizesailor is offline   Reply With Quote
Old 01-10-2012, 19:23   #9
Senior Cruiser
 
Captain Bill's Avatar

Cruisers Forum Supporter

Join Date: Apr 2008
Location: On the boat
Boat: Endeavourcat Sailcat 44
Posts: 2,313
Re: TDS Water Quality Tester

Quote:
Originally Posted by silverp40 View Post
All right, can it tell me if my water filter works or needs changing?
NO! I hope that is clear enough.
__________________
Captain Bill is offline   Reply With Quote
Old 01-10-2012, 20:39   #10
Registered User
 
silverp40's Avatar

Join Date: Jan 2010
Location: Usually where the boat is...
Boat: Pearson 40
Posts: 514
Images: 7
Re: TDS Water Quality Tester

Partial Quote from EPA Website:

"The EPA Secondary Regulations advise a maximum contamination level (MCL) of 500mg/liter (500 parts per million (ppm)) for TDS. Numerous water supplies exceed this level. When TDS levels exceed 1000mg/L it is generally considered unfit for human consumption. A high level of TDS is an indicator of potential concerns, and warrants further investigation. Most often, high levels of TDS are caused by the presence of potassium, chlorides and sodium. These ions have little or no short-term effects, but toxic ions (lead arsenic, cadmium, nitrate and others) may also be dissolved in the water."

Ok, so we are in west Guatemala filling up tanks from the local town water supply that's been there for about 300 years via jerry cans. What means do I have to do a quick test of any kind and see if it is worth shlepping it back to the tanks? Looks all right, smells ok, locals say it's fine but they've been drinking it for years...and no labs anywhere for testing.

So if a theoretical TDS meter said about 300ppm and I take the water, would I make a mistake? I do need the water -we are quite low.
__________________
silverp40 is offline   Reply With Quote
Old 01-10-2012, 21:18   #11
Registered User
 
S/V Illusion's Avatar

Join Date: Oct 2007
Location: Lakewood Ranch, FLORIDA
Boat: Alden 50, Sarasota, Florida
Posts: 1,692
Re: TDS Water Quality Tester

Quote:
Originally Posted by silverp40 View Post
Partial Quote from EPA Website:

"The EPA Secondary Regulations advise a maximum contamination level (MCL) of 500mg/liter (500 parts per million (ppm)) for TDS. Numerous water supplies exceed this level. When TDS levels exceed 1000mg/L it is generally considered unfit for human consumption. A high level of TDS is an indicator of potential concerns, and warrants further investigation. Most often, high levels of TDS are caused by the presence of potassium, chlorides and sodium. These ions have little or no short-term effects, but toxic ions (lead arsenic, cadmium, nitrate and others) may also be dissolved in the water."

Ok, so we are in west Guatemala filling up tanks from the local town water supply that's been there for about 300 years via jerry cans. What means do I have to do a quick test of any kind and see if it is worth shlepping it back to the tanks? Looks all right, smells ok, locals say it's fine but they've been drinking it for years...and no labs anywhere for testing.

So if a theoretical TDS meter said about 300ppm and I take the water, would I make a mistake? I do need the water -we are quite low.
Again, TDS is not an indicator of "safe". Just re-read the EPA reference
carefully. If you doubt the quality of the water and have no means of having it tested, it really comes down to what Clint Eastwood said - "do you feel lucky punk?" My experience is that there is always a MD or local health facility in even the most remote places and they would be your best source of advice.

I'd also mention that running the water through a carbon filter doesn't disinfect anything but only removes that which may taste bad thereby again providing a false sense of security.
__________________
S/V Illusion is offline   Reply With Quote
Old 01-10-2012, 21:53   #12
Registered User

Join Date: Dec 2009
Posts: 3,016
Images: 4
Re: TDS Water Quality Tester

Filter it to remove *solids*. Then a carbon filter if it smells bad. Then* chlorinate it in the jerry cans. Let it stand for a day. Then test for saltiness. You can taste saltiness when the TDS nears unsafe levels near 1000ppm.

In suspect areas there should be a 'taste' of chlorination in your tank water. That can be removed by simply letting the drinking water stand for a hour or with another carbon filter. Or just drink it if you are not a sissy.

That is my somewhat informed decision. The false belief that filters, either particulate or carbon, purify water of pathogens is common among cruisers. Cloudiness and bad taste never hurt anyone much. The unfilterable pathogens can kill.

* Chlorination of cloudy water is nearly worthlessas pathogens can hide in the solids.
__________________
daddle is offline   Reply With Quote
Old 02-10-2012, 16:54   #13
Registered User
 
silverp40's Avatar

Join Date: Jan 2010
Location: Usually where the boat is...
Boat: Pearson 40
Posts: 514
Images: 7
Re: TDS Water Quality Tester

Thank you all for your generous help: daddle, Illusion, Don and belizesailor!
__________________
silverp40 is offline   Reply With Quote
Old 03-10-2012, 00:34   #14
Senior Cruiser
 
bstreep's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Location: San Antonio, TX/Port Aransas, TX
Boat: 1990 Macintosh 47, "Merlin"
Posts: 2,274
Re: TDS Water Quality Tester

Just one more, from a biologist. TDS is a good measure of dissolved solids in water. It is a terrible/inappropriate instrument for the quality of your drinking water. For measuring the output of a reverse osmosis system, it's invaluable, and cheap. For determining whether or not to drink water in Mexico? Worthless.
__________________
Bill Streep
San Antonio/Port Aransas, TX
bstreep is offline   Reply With Quote
Old 03-10-2012, 07:42   #15
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,571
Images: 240
Re: TDS Water Quality Tester

Quote:
Originally Posted by daddle View Post
TDS has little to do with water-borne pathogens. Need a lab for that. The meter is for monitoring RO performance in removing *dissolved* minerals, principally salts, not solid living things or toxins ...
True, but if the R/O membrane is rejecting salt, it's likely rejecting most bacteria & virus pathogens, which are (almost) all larger than a dissolved salt molecule. Hence a TDS meter is useful for testing R/O output quality.
__________________

__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Reply

Tags
water

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 22:44.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.