Water Testing Tool or Kit Recommendations ?

[msulc]

Hi, I am preparing to test out a watermaker that came with my boat about 1 1/2 years ago that was supposedly in pickled condition.

Other than taste testing, I was wondering if anyone has recommendations on what type of testing kit or tool to use to test the salinity or bacteria in the water.

Thanks!!!
Marty

[Bergovoy]

they make a tds meter to determine the amount of Total Dissolved Solids in the water. but smell is one of the better test kits...

I saw those meters online or at home depot, and they run between $25-75

and i dont think it matters which one you get as you arent looking for a specific reading, other then zero, or as close to zero as you can get...

normal drinking water at my house is around 350ppm

[svstrider]

I am sure some one will correct me if I am wrong BUT I think a sample tastes OK to humans if there is less than 900 ppm total dissolved solids (TDS) but my water maker says to not tank the product water until TDS is less than 500 ppm.

The usual drill is to LOOK, SMELL, TASTE and if those are all OK then TEST. It usually tastes a hell of a lot better than town water on the Gold Coast in OZ.

[Bergovoy]

you can actually taste the waste water, there is nothing in there that wasnt in the origianal water right?

so, give that a taste and maybe measure it with a tds meter...

[Mark Zarley]

I do not think it would be wise to taste your watermakers "regect water". A molecule of salt is very small. Bacteria are "huge" in comparsion. Therefore if you can remove enough salt molecules to the magic 500ppm's number, in the process you have also filtered out all the bacteria which is then dumped overboard with the "reject water" . It is just that simple.

[Bergovoy]

yea, sorry, I am still thinking about my HOUSE wate filter... so yea, dont be drinking your reject water from a de salinator, or lake or stream/untreated water...

[msulc]

Thanks for the advice. So it just seems like I need a TDS meter. Does it really matter how fancy they are? Here's one on amazon for $26. Is that all I need?

Amazon.com: HM Digital Handheld TDS Tester Model TDS-3: Home Improvement

[Tellie]

Originally Posted by msulc

Thanks for the advice. So it just seems like I need a TDS meter. Does it really matter how fancy they are? Here's one on amazon for $26. Is that all I need?

Amazon.com: HM Digital Handheld TDS Tester Model TDS-3: Home Improvement

That tester is fine for the average boater with a watermaker. Usually they are fairly accurate right from the factory. Many times they send a small solution in a foil pack to calibrate the TDS meters accuracy.
The bigger question is have you thoroughly read the recommissioning procedure for your watermaker? This is important to understand omake sure the results you are getting are accurate and that you don't do any damage to the membrane when first starting the unit up after 1 1/2 years.
A TDS reading is a good start. Depending on where you are testing the system for the first time will make a difference in the readings. The only true test is in the water you will be most using the waternaker in. This is not always possible so fudge figures come into play. But for basic understanding let's assume good off shore water. Salinity and temperature are big factors in the TDS reading. But if you are reading around 200-300 PPM your membrane is probably in very good condition. If you are consistently getting over 500 PPM then there is the possibility that the membrane is going south soon. But not always. Another factor to be considered is if the watermaker is producing the proper pressures and flows. Worn feed pumps, lift pumps, high pressure pumps, adequate electrical feds and improper or corroded connections will all contribute to high TDS readings. So before you jump to the conclusion the membrane is at fault you need to make sure the entire system is operating to specs. Lets us know what make and model you watermaker is.

[msulc]

Thanks for the responses! We have the PUR POWERSURVIVOR II Watermaker. We atually don't plan on using it for water for 9 months, but I am afraid the longer I let it sit in the boat the more chance the membrane would have issues later. We will be heading from Charleston, SC to the Annapolis around April, and I was planning on testing it in the ocean if conditions were ok. I don't think I should be testing it in the Cooper River in Charleston. I have started looking at the manual but have not read much yet.

[Auspicious]

Originally Posted by Mark Zarley

A molecule of salt is very small. Bacteria are "huge" in comparsion. Therefore if you can remove enough salt molecules to the magic 500ppm's number, in the process you have also filtered out all the bacteria which is then dumped overboard with the "reject water" . It is just that simple.

True only as far as it goes. Bacteria can grow in water tanks and--more likely--in water distribution lines and faucet screens.

You might consider getting a test kit from Aerobiology Laboratories ( Aerobiology Laboratories - Welcome )
Suzanne S. Blevins, B.S., SM(ASCP)
Laboratory Director
43760 Trade Center Place, Suite 100
Dulles, Virginia 20166
877 648 9150

I have no financial connection - just used them to test my own boat.

[Minggat]

Originally Posted by Bergovoy

you can actually taste the waste water, there is nothing in there that wasnt in the origianal water right?

so, give that a taste and maybe measure it with a tds meter...

36 years of water treatment here. Not that it really comes into play here.

Ok, so what are you trying to accomplish by tasting the reject water? Your gag response? Other than that, tasting the concentrate/brine/reject/waste is not the same as drinking it, and one taste will have you... well... gaging anyway.

[Bergovoy]

again, that comment was superceeded by my clarification... I have only used ro systems in houses hooked up to the drinking water tap...

so, NO, DO NOT DRINK or TASTE the REJECT WATER from a desalinator... yuck


the reject water from tap water is yucky, but not gag worthy...

[SvenG]

We have the watermaker in the garage and will be working on installing it after we get Senta II back from the spa.

I assume the reject water is the initial water produced ? If it comes from the fresh water side of the membrane how did the salt get there ? Maybe I'm missing some major point here.

Anyway, what I'm wondering is if it might make sense to use the reject water for flushing the head to minimize salt water head odors ? IOW install a small separate reject water tank that is only used for head flushing ? If it is somehow really briney that doesn't make any sense, but if it is just not very tasty for whatever reason then it might be workable ?

Thanks,



-Sven

[Minggat]

Sorry I don't see the thread where salt is getting into the product stream, but it is negligable unless there is an o-ring failure somewhere. Initial water produced, while not yet up to quality, is a seperate stream from the reject, so no on that point.

In the RO industry, another word for reject is concentrate. That term can help to explain what's going on. Just to work in round numbers, you can count on the concentrate being twice as briney as the seawater feeding your desal unit.

You'd be making a counter productive move if you're trying to get rid of odors caused by seawater.

[SvenG]

Originally Posted by Minggat

In the RO industry, another word for reject is concentrate. That term can help to explain what's going on. Just to work in round numbers, you can count on the concentrate being twice as briney as the seawater feeding your desal unit.

Ok that makes a lot more sense. What threw me off was the suggestion to taste the reject (since retracted). I thought that referred to the initial produced desalinated water that you would reject (why else would you taste it ?).

So now that that issue has been straightened out. The initial water produced by the desalinator, it is rejected, right ? That's the water I'm suggesting using for flush water.

Does it make more sense now ?

Thanks,



-Sven