Water Quality: Testing, Filters for, and Purification of Drinking, Ground and Pool Water » Chlorine Testing

Liquid Reagent Turns Yellow in Presence of Chlorine

Water Testing Blog — Tue, 31 Jan 2012 13:03:15 +0000

Today’s inquiry came to us from ‘Kishore’ who asked a question about a liquid test reagent that turned yellow when added to a sample of water containing chlorine-based water disinfection tablets.

Dear Sir, I mixed chlorine tablets(water purification Tablets) in water. my friend taken water in Test tube. mixed one drop of liquid then water color changed in yellow. what is name of that liquid. how to by that.please can sent details.

Hello, Kishore, and thank you for the inquiry about a liquid test reagent that turns yellow in the presence of chlorine. Based upon your description we suspect your friend used a chemical called ‘OTO’ to perform the testing. OTO stands for Orthotolidine dihydrochloride. It test for total chlorine (free chlorine plus combined chlorine collectively).

Pool Test Kit for Total Chlorine & pH
Using OTO and Phenol Red

You can find OTO in most pool supply stores, as it normally comes in the more basic pool water testing kits for total chlorine and pH, the two most commonly tested pool water quality parameters.

Many companies also sell the two reagents separately since they do tend to ‘go bad’ after a year once opened and exposed to air.

If you want to perform more precise chlorine concentration testing for free chlorine, the compound most people have the most interest in (usually) when attempting to determine if water has had the proper amount of disinfectant added to it, you will want to invest in a drinking water test kit that uses DPD-based reagents. ( What is DPD? )

For an even simpler means of testing the chlorine levels in water samples you may want to consider a product such as the SenSafe Free Chlorine Water Check, an EPA Approved method for determining free chlorine concentrations in drinking water, or the WaterWorks 2 Free & Total Chlorine product that uses the same free chlorine testing method as the SenSafe Free Chlorine Water Check and also includes a separate test area for total chlorine.

Want to know more about the differences between free and total chlorine? Check out an article called Free Chlorine, Combined Chlorine, Total Chlorine.

One more thing about OTO before we go: We have heard that some countries have outlawed its use due to scientists having evidence that it may cause cancer in humans… so check local laws before making a purchase!

We hope this helps!

Turns Red When Mixed With Chlorinated Water — Leak Detection

Water Testing Blog — Tue, 17 Jan 2012 18:16:56 +0000

Every once in a while we get a question about a topic related to water quality, but not quite a water quality question… so today’s question came to us from ‘Michael’ who asked,

I need to purchase a quick test means to locate water leaks in supply pipes to my residential water service meter. The county water uses a small tear able foil packet of chemicals that turns red when mixed with chlorinated water. My home has very low water pressure and volume, we are serviced by an extremely old and much damaged 2″ pvc line serviced by the Logan County PSD, Logan WV. The PSD does not have the time or personnel to investigate all of the water puddles located in the community where I live. I would like to be able to quickly and safely test any ground water in the hope of finding where the line rupture is.

Thank you, Michael, for this inquiry. From the sounds of things your local water department uses DPD powder pillows or tablets to investigate the nature of puddles suspected to have formed as a result of leaks in municipal water lines. The chemical DPD turns various shades of pink through dark red in the presence of oxidizers such as chlorine, bromine, ozone, etc.

DPD Test Tablets
DPD-1 & DPD-3 for Chlorine Testing

Where can the average citizen get DPD?

Chemical supply houses often carry DPD powder and/or tablets in bulk and many swimming pool stores tend to carry DPD powder pillows and tablets intended to work with swimming pool test kits.

For what you want to do, though, we suggest you look more closely at DPD powder. Specifically we think you should focus your acquisition efforts on DPD-4, a compound which will detect both free chlorine and combined chlorine in a water sample. This matters because once water treated with free chlorine exits a controlled environment (i.e. leaves the pipe through a crack, fissure, etc.) the free chlorine will immediately begin acting on any and everything in its environment… and that will result in only combined chlorine possibly reaching the surface and creating a pool of water.

Problems with testing puddles for chlorine?

While not totally impossible that a pool of chlorinated water could potentially wind up on the surface over or near a leak from a chlorinated municipal water line, we believe that only a good sized leak could produce water in the volume required to get water containing highly reactive chlorine molecules through contaminant filled soil and up to the surface — with readable/detectable chlorine residual levels high enough to detect visually (or with a portable meter) using DPD.

But, since your local water department does it, either your water line infrastructure routinely has large leaks or its water lines lie very close to the surface. Either way, a swimming pool supply company called In the Swim carries DPD-1 tablets and DPD-3 tablets.

Crushing (carefully) and then mixing them (carefully) in equal parts should enable you to create your own version of DPD-4, but to play it safe we suggest using the appropriate amount of DPD-1 in a 10 mL sample of water and then using the DPD-3 in that same sample — per the ‘accepted’ procedures for free and total chlorine concentration determination.

Concerned About Bacteria in Restaurant Setting

Water Testing Blog — Fri, 18 Nov 2011 21:52:58 +0000

Web sites have flaunted the results of studies about bacteria on and around the ice machines and soda fountains in the food service industry (especially the self-service ones. Yuck!) but today’s email inquiry comes to us from ‘Jacky’ who said,

“My friends and I own a small eatery with a bed-n-breakfast in the mountains and we have water from the town. Every once in a while the news tells us to boil until further notice. The last time it happpened a customer asked how long they could have been drinking bacteria water before the news told us to boil the water. I said we don’t know and they said we should know that sort of thing before we serve people food and drink. How long COULD the water have been bad?”

From the sounds of things you had a real snot eating or staying in your place. We hope he/she at least tipped well and didn’t cause you any other grief!

Regarding the answer to the question asked, you will have to talk to the town water department and ask them for information on their bacteria testing policies and public notification policies since some municipal water systems have tighter, more stringent testing requirements than others — but none can get any looser than those set by the State & Federal Governments.

Regular testing for bacteria?

We assure you that your local water department, if it follows State and Federal Water Treatment & Testing Guidelines, performs regular testing for bacteria, testing for chlorine and tests for a host of other important water quality contaminants and water quality parameters on a regular basis.

Test Kit for 97 Water Quality Parameters

If you want more detailed information on the steps used by your local water company to protect you from bacteria and other unwanted drinking water contaminants, we suggest that you contact your local water department directly.

As we mentioned, city and municipal water departments take specific, regulated steps to protect their customers from bacterial contamination… but even in the best of circumstances sometimes things happen which could possibly put those customers at risk.

Water main breaks between the water treatment plant and customers’ homes as well as unexpected equipment failures at the water treatment plant can both certainly happen at any time and both may result in opportunities for bacteria to enter the drinking water supply.

Personal protection against bacterial contamination?

Recently a number of folks have started installing UV water sterilizers like the Crystal Quest UV 6 in their homes as a final layer of protection against bacterial contamination. These devices render bacteria unable to reproduce by exposing the unwanted critters to a specific wavelength of UV light.

Crystal Quest UV-6 Water Sterilizer

So, while the devices do not necessarily kill the bacteria right away, UV water sterilizers like the Crystal Quest UV 6, when used in the right application, make certain the organisms do not have a chance to multiply and create problems for those who ingest them.

Please note, however, that UV water sterilizers should NOT get used as the first line of defense against bacteria when dealing with untreated and/or unfiltered water.

Why? Because UV water sterilizers can do nothing to remove unwanted particles, solids and/or chemical contaminants. To remove things of that nature one should consider a unit that uses activated carbon, reverse osmosis, ultrafiltration, etc.

WaterFilters.Net carries a large selection of water filter systems and replacement water filters for use in private residences as well as a wide range of commercial applications.

While on the topic of commercial water filters…

Jacky had concerns about water quality in a commercial setting so it only makes sense that we end this article by mentioning the CQE-UV-00105, a commercial UV water sterilizer with a flow rate greater than 22 GPM.

Crystal Quest CQE-UV-00105

Do the DPD Tablets Work in Hach Meters?

Water Testing Blog — Thu, 10 Nov 2011 13:03:00 +0000

Today’s inquiry comes to us from a woman serving her country in the United States Navy. ‘Ronda’ had a question about the DPD products she had seen on our web site.

“Do your DPD Chlorine tabs work in Hach equipment?”

Good afternoon, Ronda, and thank you for this inquiry. When weighing the different DPD options (tablets, powders, reagentstrips, etc.) make sure you note the sample size that each test method will work in. As a general rule most devices that use DPD as a reagent will have 10 mL sample sizes, but we have also seen devices that use 15 mL sample sizes, 7 mL sample sizes and 20 mL sample sizes.

Check your machine’s manual to find out what sample size it takes. In order to remain compliant with whatever drinking water directives you follow you will need to match up the sample size w/ the correct reagent amount.

Specifically, though, you asked about the DPD tablets for chlorine testing that we have shown on our site and as far as we know all of the DPD products we have shown on our site work for 10 mL samples — except for the eXact Micro DPD products which work in smaller samples.

Two 10-mL Tablets/Strips/Powders for a 20-mL Sample?

While in theory that would work, definitely check your approved testing method to see if it expressly forbids that sort of thing and/or if it specifically calls for a brand or type of chlorine reagent delivery method. In the past we have seen where testing protocols have gotten so granular that they call out not only the type of DPD used, but also the brand of the test meter and DPD used for chlorine testing.

(100) DPD #1 Tablets
(1,000) DPD #1 Tablets

(100) DPD #3 Tablets
(1,000) DPD #3 Tablets

How Can I Check to See if My Water Filter is Working?

Water Testing Blog — Sun, 02 Oct 2011 13:33:38 +0000

Anyone that has taken the initiative to install a water filter or water purification device/system in their home deserves a bit of praise… and those that continue to take an interest in the quality of their water after installing a water treatment system deserve even MORE for their efforts.

As an example, ‘J. Mampilly’ from India installed a system and now seeks to determine if he has installed the correct unit. He asked,

I would like to know about how i can confirm the effectiveness of my water purifier. Labs in India that can certify and throw light on the camparative quality of water before and after using a water purifier. Thank You

Unfortunately we do not have familiarity with water testing laboratories in India and cannot directly assist with this situation. We can suggest, however, that you contact your local health department and ask them for a list of certified water testing laboratories in your area.

Coliform Bacteria Test Kit

Before…

In order to know what type of filter or what filtering capabilities you should purchase, invest (yes, we said invest) in a thorough water analysis performed by a qualified water testing laboratory. Here, again, we suggest contacting your local board of health and asking them, for a list of certified drinking water testing labs. Alternatively, or if no labs exist in your immediate vicinity, you can use the services of accredited water testing companies such as National Testing Labs.

No matter what, though, always have your water tested BEFORE deciding on a water treatment system. Oh, and one more thing: Don’t think for one second that a salesperson doing an in-home water test has the same water testing tools or qualifications as a reputable water testing laboratory. Remember: 99% of all salespeople attempt to sell things and not accurately analyze a situation — especially if accurately diagnosing a situation could cost them a sale!

Simple Test Kit for
Total Dissolved Solids

And after!

As ‘J. Mampilly’ has done, we should ALL take an interest in comparing the quality of water that comes out of our water filter systems. Only then will we know if the money we invested in (not spent on!) a quality drinking water filter system performs as expected.

Testing water quality beforehand gives us not only an idea of what we need to filter out of our water, but also a checklist of water quality parameters to monitor post-filtration. Should follow up water testing reveal that these ‘issues’ did not get corrected or suddenly show up months after the installation of a water system, perhaps the water filter has stopped working or never really worked properly in the first place and needs service of some sort.

And in conclusion…

Many people go through life ‘deaf, dumb and blind’ when it comes to the quality of their water — until an (initially) unexplainable health problem pops into their life. Then, and unfortunately sometimes too late, those same people get very interested in the quality of their water and want to punish or otherwise penalize others for allowing them to consume tainted, polluted and/or contaminated drinking water.

Although we feel much sympathy for the victims of poor quality drinking water, most of us here in the United States have the ability to at least once every great while perform basic testing for critical water quality parameters such as heavy metals (i.e. lead, mercury, copper, iron, etc.), coliform bacteria, pesticides (i.e. atrazine and simazine), chlorine levels (free and/or total), total hardness, total dissolved solids, and many others.

Many times the contaminants in a water supply will have no taste, carry no odor and not appear before the naked eye. Only testing will alert you to their presence.

Free Chlorine Levels in Irrigation Water

Water Testing Blog — Tue, 26 Jul 2011 02:01:08 +0000

Today’s question comes from ‘Mohamed’ who asked, “How much should be the free chlorine in the irrigation water? We are treating sewage water and sending it to farm lands. What is the international standard of the irrigation water in respect to free chlorine?”

WaterWorks 2 Free & Total Chlorine Test Kit

We do not know of an International Standard for free chlorine levels in irrigation water but we do know that most States in the US require wastewater treatment plants to neutralize TOTAL chlorine levels before discharging water into the environment and that wastewater treatment facilities must test for total chlorine residuals in their effluent streams on a regular basis to make sure the chlorine concentrations stay virtually non-existent.

Why worry about chlorine in the environment?

If allowed to enter the environment chlorine can and will effectively kill or damage biological organisms that it comes in contact with. In great enough concentrations chlorine will wipe out all plant life in a body of water as well as any animals or fish in the water.

We use chlorine to render safe (i.e. KILL) biological contaminants in our drinking water and if released into a natural habitat the chlorine will render safe (i.e. KILL) any and all plant an animal life until it loses its effectiveness.

Testing for free & total chlorine?

Whether you prefer test strips, wet chemistry kits or a water testing meter… you have plenty of choices when it comes to testing for both free and total chlorine levels in drinking and treated waste water.

eXact Chlorine Photometer

EPA Approved Free Chlorine Test

Taylor Fas – Dpd Titration

Filter to Remove Chloramines

Water Testing Blog — Fri, 22 Jul 2011 13:03:09 +0000

Do not let a clever sales pitch or catchy marketing jingle fool you. Many common drinking water filter systems do NOTHING to remove or reduce chloramines in water. They simply lack the technology in their filtration media to do so.

We mentioned this filter (the Pentek ChlorPlus) in the past and now feel the need to mention it again since we continue to receive inquiries from people asking why their water filters fail to remove all of the chlorine smell from their water.

The majority of water filters readily available in the marketplace do NOT remove chloramines, also known as combined chlorine. Most carbon filters remove free chlorine only. It takes a specialized type of filter like the Pentek ChlorPlus to cleanse water of unwanted chloramines.

Does my water contain chloramines?

Whether your municipal water system uses free chlorine or chloramines as its primary sanitizing agent we cannot say, but in either case your water will certainly contain chloramines. Unsure why? Take a look at this brief tutorial on free chlorine, total chlorine and combined chlorine.

That’s just a cartridge… What sort of housing does it go in?

A very keen observation followed by a very good question! The Pentek ChlorPlus filter for chloramine removal fits in most standard sized 10″ (by 2.5″) filter housings including, but not limited to, models manufactured by companies like Pentek, Ametek, US Filter, Bruner, American Plumber, Cuno, Filterite, Keystone, Water Resources and most Harmsco filter housings.

As always before purchasing a replacement cartridge for your water filter system, check, double check and TRIPLE check to make sure your housing will accommodate the filter cartridge you wish to buy!

Chlorine Testing Meter for Swimming Pool?

Water Testing Blog — Fri, 01 Jul 2011 13:03:03 +0000

As we expected, the number of questions we received recently about swimming pool water has definitely increased. Today’s inquiry comes from a Water Testing Blog reader who hails from Pakistan and he/she asked:

Dear Sir/Madam,
hope you will be fine.i need some information regarding digital chlorine tester for swimming pool water .i read about extech cl200 testing metre.kindly send me the literature and price for it .
thanks
an early response is appreciable
farhan

Now before any of you go and criticize this person’s grammatical skills when typing in English, think more about the person’s commitment to keeping a proper chlorine level in swimming pool and the time it took to submit a question to this site.

ExTech CL200 Total Chlorine
Testing Meter for Water

ExTech CL203 Total Chlorine
Test Reagent Tablets

WE commend ‘Farhan’ for his/her efforts and for transcending the language barrier to ask a question about proper chlorine testing in pool water.

On the topic of the “Extech 1200C” for chlorine testing in pool water, we took a look at the ExTech web site and did not find a meter in the chlorine/fluoride in water detection called the ‘Extech 1200C’… so we found ourselves a bit puzzled by your question.

We DID, however, see the ExTech CL200 Chlorine Testing Meter which uses Extech (CL203) Exstik ExTab™ Chlorine Reagent Tablets, a undoubtedly a proprietary blend of DPD-1 & DPD-3 reagents, to test for ONLY total chlorine concentrations in water.

The obvious problem we see with this meter for pool water testing, despite its USEPA credentials for total chlorine testing (in waste water), deal with the meter’s INability to test for free chlorine concentrations in water.

Proper Pool Water Testing Requires Free AND Total Chlorine Testing!

That heading said it all. Proper pool water care requires both free AND total chlorine testing.

Why? Quite simply, it does little good for the sanitation of a pool to have an in-range total chlorine reading with a very low, or non-existent, free chlorine reading. When that happens the pool contains mostly, if not entirely, chloramines (aka: combined/used chlorine molecules) which possess very little (limited) oxidizing power… and limited oxidizing power means limited sanitizing capabilities.

Improperly sanitized pool water can EASILY become a home in which various bacteria, parasites and viral ‘issues’ which will flourish, breed and infect swimmers if left unchecked.

Repeated Moral of the Story

Invest in a meter that test for both total chlorine concentrations AND free chlorine concentrations.

We suggest using a meter like the eXact Micro 7+ Pool & Spa Meter because it tests for not only free AND total chlorine, but also for Total Alkalinity, Bromine, Calcium Hardness, Copper, Ozone, Permanganate, and pH… all with the same meter!

Earlier we talked about the Extech’s USEPA credentials so naturally we figure you want to know if the eXact Micro 7+ Meter has credentials, too — and it does! When used with DPD chemistry (and the appropriate procedures, of course) the meter qualifies as an EPA Compliant device for testing free an total chlorine in drinking water.

“But Wait! There’s More!” Screamed the Announcer

As an added bonus, the eXact Micro 7+ Pool Meter also has the ability to test for Ammonia, Chloride/Salt, Chlorine Dioxide, Chromium Hexavalent, Cyanuric Acid, Iodine, Iron, Low Range Total Hardness, Manganese, Nitrate, Nitrite, Acid pH, Alkali pH, Potassium, Sulfate, Sulfide, and Turbidity — when operated in ‘% Transmission’ mode with the appropriate eXact Micro 7+ Reagent Strips.

eXact Micro 7+ Pool Testing Meter

eXact Micro 7+ ReagentStrips

Question: Why is My Lawn Yellow?

Water Testing Blog — Wed, 15 Jun 2011 01:01:12 +0000

Today’s question comes from a woman in Illinois named ‘Gretchen246′ who asked a very interesting question… about her lawn.

“Why is my lawn green? A healthy lawn is the sign of a healthy home and my lawn is yellow. Allthe lawns here are yellow and we all fertilize and feed and do all we’resupposed to but the lawns are still yellow. Could it be the water?”

Sad to say, but the little kid in us wants to say, ” Gretchen, your neighborhood needs a leash law to keep wandering dogs from peeing all over your lawns!” Ha ha. Yep. The kid in us has not, yet, grown up all the way… and we hope it never does!

On a more serious note, if every lawn in your neighborhood has the same issue (bad grass), then it stands to reason that all of your lawns have at least SOMEthing in common. Typically all yards in a development will share a similar soil type (i.e. composition, pH, etc.), environmental conditions (rainfall, amount of sunlight, etc.) and quality of water used to keep them hydrated.

Since we know very little about soil we will pass on the opportunity to discuss that topic and move in for the kill on a topic we DO know something about: Water. Since you say your lawns stay yellow, a sure sign of a dead or dying lawn, perhaps your lawns don’t particularly care for something in the water?

As our first guess, we cast our vote for chlorine. Most municipal water systems use a form of chlorine to keep biological contaminants from growing in the water and water lines. Once out of the water line, however, chlorine will continue to wage war on biological organism… like the grass in your lawn.

Chlorine in my water?

How do you know if your tap water contains chlorine? Perform a simple test for chlorine using a product such as the WaterWorks 2 Free & Total Chlorine Test Strip. We like this product because it provides reliable test results for both free and total chlorine concentrations in water at the same time and in just a few minutes.

There’s chlorine in my water… Now what?

Well if the chlorine poses a problem (i.e. it kills your grass!) then we heartily suggest removing it from the water you use on your lawn. The products below from Gar’n'Gro should have the ability to help with that task.

Gard’n'Gro Chlorine Removal Filter	Pre-Filter for Gard’n'Gro Filter
Replacement Gard’n'Gro Chlorine Filter	Replacement Gard’n'Gro Pre-Filter

For those interesting removing chlorine from their drinking water, you may want to consider installing a simple, yet effective, faucet filter such as the Crystal Quest W2 in your kitchen.