Thanks dittohead. Yes I'm kinda sorta familiar with the manganese dioxide coated zeolyte stuff as opposed to the solid manganese dioxide. When I saw how heavy that Filox stuff is, it made me think of trying to backwash a canister full of iron filings. I'll order the KAR test asap and post the results. By the way, the product catalog on your website is incredibly informative and I will be studying it. I really appreciate the guidance from everyone here so far, by the way!
Backwashing carbon filter?
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ditttohead
Water systems designer, R&D
Thanks so much. I used to be a big proponent of Filox/Pyrolox, not so much anymore. Many of our customers would separate it into two systems so they could accommodate the high backwash rates... not a great solution but it worked.
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I am not a pro. This is my take on it. There are probably some things I have missed.
List anything which has an MCL where you have that amount or more. I would also list things that are more than half of the MCL.
Always include numbers for hardness grains, iron, manganese, pH. Those are things commonly treated for. Not commonly in need of treatment, but which could be would include salinity, silica. Ryznar corrosivity. I probably missed some worthwhile thing to check.
Any number with a less than sign ("<") in front of the number is below the test sensitivity. No need to include those I think, unless it is something like iron.
Another way is to blank the name and maybe other non-number things, and upload a file with the modified data. Most people will not know how to do that. Note that your name and address are included. While some people upload the whole report as a PDF, I suggest you don't do it that way.
Indicate if the reading is for your raw, untreated water, or if not, what treatment has been applied.
List anything which has an MCL where you have that amount or more. I would also list things that are more than half of the MCL.
Always include numbers for hardness grains, iron, manganese, pH. Those are things commonly treated for. Not commonly in need of treatment, but which could be would include salinity, silica. Ryznar corrosivity. I probably missed some worthwhile thing to check.
Any number with a less than sign ("<") in front of the number is below the test sensitivity. No need to include those I think, unless it is something like iron.
Another way is to blank the name and maybe other non-number things, and upload a file with the modified data. Most people will not know how to do that. Note that your name and address are included. While some people upload the whole report as a PDF, I suggest you don't do it that way.
Indicate if the reading is for your raw, untreated water, or if not, what treatment has been applied.
I used the basic KAR test kit that tests for all kinds of stuff. I only included results that are above half of MCL. The water at this house currently has no filtration of any kind:
calcium 109 mg/L
Iron 2.86 mg/L
magnesium 5.7 mg/L
Manganese 0.020 mg/L
Potassium 2.6 mg/L
Silicon 10.6 mg/L
sodium 16.8 mg/L (MCL= 20 mg/L)
coliform positive (but no indication of how much)
alkalinity (as CaCO3) 292 mg/L
bicarbonate (as CaCO#) 291 mg/L
carbonate (as CaCO3) 0.69 mg/L
clarity <100 mm
color 50 color units (MCM = 15)
conductivity 611 micromhos/cm
aggressive corrosivity 12.3
Langelier corrosivity 0.4 S.U.
Ryznar corrosivity 6.5 S.U.
Hardness (as CaCO3) 296 mg/L (17.3 GPG)
Ph 7.4 S.U.
resistivity 1640 ohms/cm
salinity 0.306 ppt
silica 22.7 mg/L
sodium ads. ratio, adjusted 0.67
sodium adsorption ratio 0.42
turbidity 32.1 NTU (MCL = 0.3)
total dissolved solids 410 mg/L (MCL = 500 mg/L)
calcium 109 mg/L
Iron 2.86 mg/L
magnesium 5.7 mg/L
Manganese 0.020 mg/L
Potassium 2.6 mg/L
Silicon 10.6 mg/L
sodium 16.8 mg/L (MCL= 20 mg/L)
coliform positive (but no indication of how much)
alkalinity (as CaCO3) 292 mg/L
bicarbonate (as CaCO#) 291 mg/L
carbonate (as CaCO3) 0.69 mg/L
clarity <100 mm
color 50 color units (MCM = 15)
conductivity 611 micromhos/cm
aggressive corrosivity 12.3
Langelier corrosivity 0.4 S.U.
Ryznar corrosivity 6.5 S.U.
Hardness (as CaCO3) 296 mg/L (17.3 GPG)
Ph 7.4 S.U.
resistivity 1640 ohms/cm
salinity 0.306 ppt
silica 22.7 mg/L
sodium ads. ratio, adjusted 0.67
sodium adsorption ratio 0.42
turbidity 32.1 NTU (MCL = 0.3)
total dissolved solids 410 mg/L (MCL = 500 mg/L)
You have some advanced stuff there, color and salinity for example. You are looking to use the water for a house including drinking water, I think.
I may be able to help with that. Submersible pump, shallow well pump, or what?
This is a submerged pump, though I don't know how deep it is. It puts out around 20-26 gpm. And although we plan on installing a RO system under the kitchen sink for drinking, I do plan on using the water inside the house and want to clean it up as much as possible.
Jeffrey Bogert
New Member
How do you plan on handling the coliform? Shock well repeat test? With the iron and bacteria have you thought about chlorination or an oxidizing system using hydrogen peroxide? Then a backwashing carbon filter and finally a softener?
http://www.terrylove.com/forums/ind...izing-extra-attention-to-4-inch-casing.65845/ is my write-up on sanitizing a deep well and plumbing. Jeffrey Bogert makes a good point in that injection, preferably followed by a contact/settling tank, can kill bacteria as well as getting rid of iron and H2S. Injection is normally followed by a backwashing GAC tank to remove the H2O2 or bleach.
Sanitizing is still good with injection, particularly after the chlorine or H2O2 has been removed. You want to kill stuff that is in your WH and plumbing too.
UV is also used to kill bacteria after other treatments.
A good sanitizing is usually quite able to handle the coliforms. In fact, the faucet you sampled from may not have been sufficiently sterilized before you drew your sample. The Kar instructions don't get into that sanitizing much IIRC.
Sanitizing is still good with injection, particularly after the chlorine or H2O2 has been removed. You want to kill stuff that is in your WH and plumbing too.
UV is also used to kill bacteria after other treatments.
A good sanitizing is usually quite able to handle the coliforms. In fact, the faucet you sampled from may not have been sufficiently sterilized before you drew your sample. The Kar instructions don't get into that sanitizing much IIRC.
Not even sure what to do yet.
The KAR instructions say to take the sample from a tap in the house. Then in the box where they say coliform is positive, they state: "39% of kit samples are tested Positive, often due to a dirty faucet aerator and/or improper sampling." They don't say anywhere on the kit instructions to scrub out the inside of the faucet before taking the sample, just that you should run the water for 10 minutes!
Since it may have been in the faucet or the lines inside the house, maybe I should take a sample right at the well and take to a local shop that can repeat the test for coliform?
What really sucks is that nobody will be able to tell me how much is there, just if it's there or not.
The KAR instructions say to take the sample from a tap in the house. Then in the box where they say coliform is positive, they state: "39% of kit samples are tested Positive, often due to a dirty faucet aerator and/or improper sampling." They don't say anywhere on the kit instructions to scrub out the inside of the faucet before taking the sample, just that you should run the water for 10 minutes!
Since it may have been in the faucet or the lines inside the house, maybe I should take a sample right at the well and take to a local shop that can repeat the test for coliform?
What really sucks is that nobody will be able to tell me how much is there, just if it's there or not.
Yeah, sorry about that. For a deep well, the strong odds are it was some sample contamination. In addition, not all coliform are pathogenic. An E Coli test is a more diagnostic test for surface contamination of a well, I think.
While I think the danger is overblown, you could drink bottle water until you feel more confident. Or sanitize your well now, and figure to sanitize at least your plumbing again after you do your plumbing work (which could bring something in).
This is one case where the county offers useful testing. That is typically about all they test for.
Here are some sampling procedures.
http://www.ugra.org/pdfs/SamplingHandout.pdf
https://clearcreekwaterworks.com/sampling-procedures/ (a bit overblown)
https://www.hach.com/asset-get.download-en.jsa?id=7639984003 page 2
Like most people, you did not do that stuff. I guess when I suggest a water test, I should probably give a tip about drawing the coliform sample. I am thinking of using this wording in the future:
While I think the danger is overblown, you could drink bottle water until you feel more confident. Or sanitize your well now, and figure to sanitize at least your plumbing again after you do your plumbing work (which could bring something in).
This is one case where the county offers useful testing. That is typically about all they test for.
Here are some sampling procedures.
http://www.ugra.org/pdfs/SamplingHandout.pdf
https://clearcreekwaterworks.com/sampling-procedures/ (a bit overblown)
https://www.hach.com/asset-get.download-en.jsa?id=7639984003 page 2
Like most people, you did not do that stuff. I guess when I suggest a water test, I should probably give a tip about drawing the coliform sample. I am thinking of using this wording in the future:
If you care about the coliform test results, care needs to be taken in sampling. http://www.ugra.org/pdfs/SamplingHandout.pdf is one description
of a method to avoid contaminating the sample.
of a method to avoid contaminating the sample.
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I'm about ready to just forget about the coliform and just use the RO filter for drinking water! But otherwise, how about the rest of the sample? Iron is lower than what came back in the other test I did, and hardness appears to be higher. Would I be best off just using a softener to handle it all or is a Katalox filter in order here?
I don't know about things like color, but that turbidity like diluted mud? I don't know. I would go with one or 2 Pentek Big Blue filter housings for 4.5 x 20 filter elements. Then maybe a Pentek DGD-2501-20 in the last housing. The first housing, if you have one, could either be empty, but I am thinking of some courser maybe 100 micron filter. What you trap initially could help decide what to put in next. A filter ideally will have a bypass. I don't have a bypass currently, but I am looking to put one in. I actually have 2 of the valves I need in place, but the actual bypass, not yet. I do keep an extra O-ring in stock before changing cartridges. My cartridges are after my backwashing iron+H2S filter. They may be overkill. I go over a year between cartridge changes. I ordered the filters before deciding to get the backwashing unit. Your KL will take out larger sediment, so a single cartridge is probably enough after the KL.
You have provided good info, and I expect you will be getting some good recommendations on KL sizing as well as other info.
And regarding the coliform, your plan sounds good to me. I would still sanitize the well and plumbing. Killing IRB in the well will reduce gunking up in the well.
In reality, it may eat on you until you get a clean coliform test. So a month after you sanitize, see what the county has to offer.
ditttohead
Water systems designer, R&D
There is a lot of "wrong" going on here. An ro is not used for coliform reduction. Coliform is not "safe". It is an indicator of a potentially non dangerous issue, not a sure fire indicator. The same way e-coli is only a likely indicator of a dangerous issue...
Take care of the coliform issue. Please go to the line provided and read the article on coliform/e coli and sanitizing I wrote a while back, this may give you a little better insight to what is going on and how to solve it. https://view.publitas.com/impact-water-products/2018-catalog-final/page/282-283
A home test kit is available, typically less than $15 and it only takes 24-48 hours. Ecoli and colifor are included in the same test, you use a UV light to determine if e coli is present. https://view.publitas.com/impact-water-products/2018-catalog-final/page/278-279
calcium 109 mg/L
Iron 2.86 mg/L High level, this should be treated... and you can double up on the coliform by chlorination/contact tank...
magnesium 5.7 mg/L
Manganese 0.020 mg/L
Potassium 2.6 mg/L
Silicon 10.6 mg/L
sodium 16.8 mg/L (MCL= 20 mg/L)
coliform positive (but no indication of how much) Needs to be treated appropriately, redundant treatment recommended as is whole house sanitization
alkalinity (as CaCO3) 292 mg/L
bicarbonate (as CaCO#) 291 mg/L
carbonate (as CaCO3) 0.69 mg/L
clarity <100 mm
color 50 color units (MCM = 15) Probably caused by the high level of iron, KL will usually take care of this. No real need for Big Blues in this application as the Hydra and KL backwashing system will negate these in most applications.
conductivity 611 micromhos/cm
aggressive corrosivity 12.3
Langelier corrosivity 0.4 S.U.
Ryznar corrosivity 6.5 S.U.
Hardness (as CaCO3) 296 mg/L (17.3 GPG) High hardness, probably should treat this with a softener
Ph 7.4 S.U.
resistivity 1640 ohms/cm
salinity 0.306 ppt
silica 22.7 mg/L high but not much you can do about this
sodium ads. ratio, adjusted 0.67
sodium adsorption ratio 0.42
turbidity 32.1 NTU (MCL = 0.3)
total dissolved solids 410 mg/L (MCL = 500 mg/L)
I dont really see anything too exciting here, a simple chlorine injection system with a baffled contact tank will take care of the majority of the iron, either a KL or Cat GAC backwashing system, I am more partial to KL since it does a better job of sediment reduction but either will do fine, followed by a softener and a whole house UV and you will have very nice water.
I would lean toward a higher rejection, higher quality RO rather than a high efficiency... a UV on the small RO would also be cheap insurance.
Take care of the coliform issue. Please go to the line provided and read the article on coliform/e coli and sanitizing I wrote a while back, this may give you a little better insight to what is going on and how to solve it. https://view.publitas.com/impact-water-products/2018-catalog-final/page/282-283
A home test kit is available, typically less than $15 and it only takes 24-48 hours. Ecoli and colifor are included in the same test, you use a UV light to determine if e coli is present. https://view.publitas.com/impact-water-products/2018-catalog-final/page/278-279
calcium 109 mg/L
Iron 2.86 mg/L High level, this should be treated... and you can double up on the coliform by chlorination/contact tank...
magnesium 5.7 mg/L
Manganese 0.020 mg/L
Potassium 2.6 mg/L
Silicon 10.6 mg/L
sodium 16.8 mg/L (MCL= 20 mg/L)
coliform positive (but no indication of how much) Needs to be treated appropriately, redundant treatment recommended as is whole house sanitization
alkalinity (as CaCO3) 292 mg/L
bicarbonate (as CaCO#) 291 mg/L
carbonate (as CaCO3) 0.69 mg/L
clarity <100 mm
color 50 color units (MCM = 15) Probably caused by the high level of iron, KL will usually take care of this. No real need for Big Blues in this application as the Hydra and KL backwashing system will negate these in most applications.
conductivity 611 micromhos/cm
aggressive corrosivity 12.3
Langelier corrosivity 0.4 S.U.
Ryznar corrosivity 6.5 S.U.
Hardness (as CaCO3) 296 mg/L (17.3 GPG) High hardness, probably should treat this with a softener
Ph 7.4 S.U.
resistivity 1640 ohms/cm
salinity 0.306 ppt
silica 22.7 mg/L high but not much you can do about this
sodium ads. ratio, adjusted 0.67
sodium adsorption ratio 0.42
turbidity 32.1 NTU (MCL = 0.3)
total dissolved solids 410 mg/L (MCL = 500 mg/L)
I dont really see anything too exciting here, a simple chlorine injection system with a baffled contact tank will take care of the majority of the iron, either a KL or Cat GAC backwashing system, I am more partial to KL since it does a better job of sediment reduction but either will do fine, followed by a softener and a whole house UV and you will have very nice water.
I would lean toward a higher rejection, higher quality RO rather than a high efficiency... a UV on the small RO would also be cheap insurance.
You don't see value in a 20 to 1 micron dual gradient cartridge?
ditttohead
Water systems designer, R&D
not really. KL will filter sediment down to 3-5 microns and is self cleaning. The contact tank sill settle out most of the heavier sediment. I should encourage the BB or other types of filtration as it would increase sales... 
It would've been really nice of the KAR people to mention cleaning the faucet or something like that in the kit instructions, instead of just stating in the results that "39% of kit samples are tested Positive, often due to a dirty faucet aerator and/or improper sampling." I guess they assume we do this all the time and should know just what to do.
Does anyone think maybe it would be a good idea if I take a sample at the spigot by the well head and then have my local health dept check it for coliform? The house has been vacant for 6 months and who knows what's growing in the faucets. At least then I'll know what is, or what isn't, present in the well itself. I'd hate to have to resort to stuff like chlorine injection and baffled contact tanks just because of a dirty faucet!
I guess my question is, what's the probability that the coliform is actually in the house/faucet and NOT in the well itself?
Does anyone think maybe it would be a good idea if I take a sample at the spigot by the well head and then have my local health dept check it for coliform? The house has been vacant for 6 months and who knows what's growing in the faucets. At least then I'll know what is, or what isn't, present in the well itself. I'd hate to have to resort to stuff like chlorine injection and baffled contact tanks just because of a dirty faucet!
I guess my question is, what's the probability that the coliform is actually in the house/faucet and NOT in the well itself?
Bannerman
Well-Known Member
If the faucet utilized to obtain the sample is the one usually supplying drinking water, that would then indicate the conditions residents have been and continue to be exposed to.
With a coliform positive result, that is a question that remains to be answered.
Asking for probabilities implies risking the faucet is the source instead of conducting additional tests to verify the source.
The home test kit Ditttohead recommended, would be a low cost method to perform additional testing.
ditttohead
Water systems designer, R&D
I recommend removing the aerator and wiping the area down with alcohol then take a sample without the aerator. Soak the aerator in alcohol to be sure it is sanitary before you reinstall it.
