Greensand Filter - Frequent Clogging

I have a greensand iron filter with an Autotrol 255 valve. The greensand filter sits between a well pressure tank and a water softener. It's being used to treat well water with an iron level of 3 PPM, and problems with iron bacteria. I had it installed 3 years ago, after running into problems with my water softener clogging every year or so.

My main problem is the greensand filter clogs every 3-4 months, causing the potassium permanganate solution to backup out of the holding tank. In order to resolve, I have to remove the venturi valve and filter screen from the Autotrol 255 assembly - and either replace or clean (with Iron Out) these 2 parts. The problem is that the inside of the valve is almost completely coated with orange sediment & sand, which I have a very hard time removing completely from the inside.

After 3 years of dealing with a mess of purple solution backup & frequent valve replacement & service calls (occasionally I can clean myself, but other times I have to have the installer out) I'm at my wit's end with this filter. The installer is now recommending a "Big Blue" cartridge sediment filter be installed between my pressure tank and the greensand filter. I'm hesitant to take his advice since he didn't recommend the sediment filter in the first place. I'm wondering if such a filter will solve my problem, or if I need to look at other alternatives (get rid of greensand altogether and go back to just a softener, or replace greensand with another iron filter)?

Any advice is greatly appreciated; I'm a first-time poster and have searched this forum and many others, but haven't found a post that exactly matches my situation.

First of all if in fact you do have "iron bacteria". A Greensand filter will not remove iron bacteria and may very well make it worse. An Autotrol valve for a greensand filter is a really bad idea! The ports become plugged with oxidized iron and as you have experienced the venturi gets plugged frequently with oxidized iron and potassium permanganate.
I would recommend getting a thorough water analysis with a TOC (total organic carbons) test for organics in the water. You can also look for bacterial iron in the toilet tank. There will be a slime buildup or an oily type film on the water that can indicate iron bacteria. Most likely much of the iron has fouled the water softener also, especially if iron bacteria is present.
There are several ways to combat this type of iron along with hydrogen sulfide.
1. Chlorine injection / retention tank and filtration tank.
2. Hydrogen peroxide injection / retention tank and filtration tank.
3. Water Right sanitizer plus water conditioning system. This system uses KDF media and a chlorine generator to kill iron bacteria and sanitize the system during regeneration.

The first step though is to get a proper water analysis from a third party lab to determine the actual water chemistry and course of treatment. You can go to www.wqa.org for a certified water treatment professional in your area.

RJ

rjh2o said:

First of all if in fact you do have "iron bacteria". A Greensand filter will not remove iron bacteria and may very well make it worse. An Autotrol valve for a greensand filter is a really bad idea! The ports become plugged with oxidized iron and as you have experienced the venturi gets plugged frequently with oxidized iron and potassium permanganate.

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Thanks very much for the reply. I don't think the iron bacteria problem is too bad, and is being kept under control by shock chlorination. I don't notice a slime buildup in the toilets unless we go a number of weeks w/o cleaning, and the water quality seems very good when all my equipment is operating well. I have not had a test for TOC level yet. re: your comment about the Autotrol valve being a bad choice for a greensand filter - what type of valve should be used instead? Does this mean that a sediment filter won't help prevent the clogging? I had the Water Right sanitizer system recommended as a replacement for my greensand filter + softener. Then I had another company recommend a Kinetico dual-tank softener (with no iron filter) as a single replacement for both. Both installers cautioned against a chlorine injection system due to cost/upkeep. Needless to say I'm quite confused!

I agree with rjh2o in part. A chlorine injection system with a retention tank is the best. The majority of the iron will settle in the retention tank which can be flushed out easily. The cost of this system may be higher upfront, but the long term cost will be lower than any other system. Any system that requires a venturi will clog over time. The small ports of a valve will also get clogged over time.

Thanks to all for the replies! I was told by several installers that chlorine injection systems are not a good idea - partly due to cost & upkeep, but also because they do nothing to treat iron bacteria problems in the well/pressure tanks/lines. They recommended periodic shock chlorination (every 6-12 months) as a better way of treating iron bacteria problems.

As for my greensand filter & the clogging problems; are the venturi clogging issues related to dissolved Iron or Iron Bacteria? I'm trying to understand if my Autotrol valve is a bad design for ANY iron problem, or if it's a bad idea due to iron bacteria or dissolved iron? The installer who recommended the Kinetico softener as the only treatment option told me that my iron levels (3 PPM) are low enough where the Kinetico softener should be able to handle without another iron treatment option.

I sell a chlorinator and retention tank for $1100 installed. You might be able to do better online. The upkeep per month runs $2.00-3.00 for chlorine. I like the chlorination system because it kills bacteria as well as oxidizes the iron and h2s. I do not recommend "shocking" the well on a regular basis. I have heard of horror stories from home owners that have done it.

All valves have ports that could get clogged with iron over time. It is build up of dissolved iron. Any water softener will remove iron, not just a Kinetico. As for the Autotrol, it is a well buildt valve and will handle the iron as long as it is maintained. That can be said about any other valve as well.

I know that around here greensand units like Sears, and others that have the Factory settings as to how long in each part of the cleaning or regen cycle last about 6-12 months and then have problems big time.
The Fleck units that can have the cleaning cycle times set on site work the best over the long run and have little challenges.

Kinetico's are good units, but if you are having iron building up in the unit that you have think of that build up in parts of a valve that you can not get to and all of it plastic parts large and small........

Flow rate is another thing that has a part to play in the working of any greensand unit.
Is this unit after the pressure tank?
Back wash rate or gallon per minute is almost double of the service flow rate, if there is not enough flow the unit will have challenges, and that might be part of the reason for the trouble that you are having with it right now.

Akpsdvan said:

Flow rate is another thing that has a part to play in the working of any greensand unit.
Is this unit after the pressure tank?
Back wash rate or gallon per minute is almost double of the service flow rate, if there is not enough flow the unit will have challenges, and that might be part of the reason for the trouble that you are having with it right now.

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The greensand filter sits after the pressure tank and before the softener. Inadequate flow rate was mentioned as a possible cause of the frequent clogging. I've about had it with the greensand filter - due to frequent service calls and the expensive media ($30+ for a canister of Potassium Permanganate at the hardware store!); however I am confused about options ranging from a solo Kinetico softener - to a $1K+ chlorination system. re: shock chlorination, while it's been recommended by 2 water treatment companies as a way to control iron bacteria, I had an experienced well contractor tell me to steer clear since he's seen it cause major issues with pipes & pumps due to loosening of sediment in the well & lines.

You could try the softener by its self, bypassing the Greensand unit and setting the softener to do all the work.
Softener will have to regen or clean more often than it is doing right now, but it will show you as to "will the softener do the job or not"
Iron X 4 + hardness = comp hardness

danimal96 said:

Inadequate flow rate was mentioned as a possible cause of the frequent clogging...

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My iron filter is a birm type and it suffers from inadequate flow rate during backwash because of the micronizer. I installed a purge valve close to the filter in the line from the precipitation tank. I flush the line to the drain frequently. a few times a year I draw down the precip tank enough so that the purge valve spurts a mix of air and water and that really cleans out the pipe.

Afterward, I override the pressure switch and backwash in spurts at 80 PSI, stopping the flow and restarting it when the PSI climbs again to 80. After that I run Super Iron Out through the system.

The Sanitizer will take care of hardness, iron, h2s and iron bacteria. Running only a softener when iron bacteria is present is a bad idea also. It will only lead to fouled resin and a worse iron problem. Chlorinating the well to remove iron bacteria is a useless waste of time and bad advice from people that refuse to take the time to address the water problems and treat them properly and your well contractor WAS right. If any chlorine got into the greensand filter when chlorinating the well then it is toast. A greensand filter will only supply 5 gpm flow rate. Piston driven valves are much better period for performance and application. Any iron filtration system requires a minimum of 30 psi to backwash properly. If you also have sand coming from the well then no system will work. Run water from an outside spigot (not treated) into a clean white bucket. Have the well cycle at least 2 times and observe if any sand settles in bottom of bucket afterword.
You are getting a lot of really bad advice from the people coming into your home. Do as I suggested earlier, go to wqa.org for a licensed professional.
The only reason anyone would use an autotrol valve as a greensand filter is because they are going CHEAP.
Get the water analysis done and let us know if in fact there is iron bacteria.
RJ

This might be a rhetorical question, but if shock chlorination is bad for your well & won't solve iron bacteria issues - then why has it been suggested by more than one company, including one which has is certified by WQA? Based on the amount of gunk it has flushed out of my system the 3x I've had it done, my instincts tell me it's NOT good for the system, yet there are "pros" out there who continue to recommend it!

I just finished cleaning out the valves inside the Autotrol assembly; as in the past they were coated with a red grainy substance, which it sounds like is oxidized iron which was not able to be purged from the unit. I'm still wondering if a sediment filter is a good idea, just to be safe?

I will contact another company for the thorough water analysis. You mentioned TOC (total organic carbons) as an indicator of iron bacteria. Any other levels I should have tested? My most recent analysis (by the company who recommended the Kinetico softener) shows only the following levels:

Hardness: 33
Iron: 3
TDS: 600
DISC: 5

Pending results of the water test, it sounds like a replacement of the greensand filter Autotrol valve (at minimum) or the entire unit (preferred?) is in order - with the replacement unit TBD based on whether or not I have iron bacteria in the water. Is this a fair summary?

Thanks again for all of the replies and advice!

What size is the softener?
What kind of control? day or meter?
Any reason that you could not bypass the iron filter and set the softener for a comp hardness of 45 grains?

Why use more equipment when less may be better?

rjh2o said:

The Sanitizer will take care of hardness, iron, h2s and iron bacteria. RJ

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I have a customer that has a Sanitizer on water that has h2s and it does not work. The Santizier will only produce chlorine during a regen cycle.

mialynette2003 said:

I have a customer that has a Sanitizer on water that has h2s and it does not work. The Santizier will only produce chlorine during a regen cycle.

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How old is the Santizier?
What media was used?

Akpsdvan said:

How old is the Santizier?
What media was used?

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I didn't sell it, but as far as I know it has the media that Water Rite makes. IIRC it's a manmade zeolite of sort. The age when I started delivering salt was about 2 years old and that was 3 years ago. It has not worked to remove the h2s but keep the water soft.

Water right sanitizers need to be checked every few years. The KDF media is what kills the iron bacteria and neutralize the chlorine. I have found many dealers do not put the KDF (min-plus) in the softener for several reasons.
1. They find the cost of KDF too expensive
2. They do not understand its use in the system
3. KDF requires high backwash flow rates so it it mis-applied frequently.

If the system was applied for PH adjustment the media is sacrificial and has to be topped off after several years.
The chlorine generator is used to sanitize the media and prevent buildup of iron bacteria on the media. Sanitizers use a form of zeolite media so it is impervious to chlorine. There is also a max amount of H2S that a sanitizer will remove.

If their sanitizer is the old ASC (2510 valve) the chlorine generator may not be working properly especially if they have run out of salt frequently.

Shock chlorinating the well is BIG band aid and as you stated causes more problems than it helps. You keep asking the same questions and we keep replying with the same answers. Do NOT buy another greensand filter or fart around with the present one. Replace it something that works. You have not done any testing or flushing of well which we suggested. Until these things are done and results confirmed all of this is moot.

RJ

RJ

Sanitizer either had CR100 or CR200 and then there is the KDF 85 for H2S and iron and as said, if the back flow is not correct or the brine draw and rinse is not the 90 minutes then the system will not work right.
They also used the Fleck 4200 valve.. they did use the 2850 for larger flows with the chlorine gen ... fun system to work on.
There are a number of things that might make the Sanitizer to fall on its face or it could be that it should have never been put in at the start.

rjh2o said:

Shock chlorinating the well is BIG band aid and as you stated causes more problems than it helps. You keep asking the same questions and we keep replying with the same answers. Do NOT buy another greensand filter or fart around with the present one. Replace it something that works. You have not done any testing or flushing of well which we suggested. Until these things are done and results confirmed all of this is moot.

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I'm lining up appointments with a few local WQA-listed installers. I will get the full water test to cover iron bacteria levels and will post the results here once I have them. I do plan on getting rid of the greensand filter, and either go with a softener-only solution or softener + non-greensand filter (depending on the results of the test). I don't recall "flushing of well" being mentioned previously - but am I correct in assuming that is a step to take if the test you suggest reveals sand in my untreated well water?

This is all well and good about the Sanitizer, but I prefer something I know from past experience that works everytime. I do not sell something that if this is that way then use this or if it is that way use that. I stay away from medias that are heavy, KDF, Filox, Pyolox...etc because most residental well I have seen don't have enough flow rate to properly backwash these medias. Chlorination is the best way to deal with h2s and high iron.