Backflusing Frequency for Sand and Carbon Filters

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GTOwagon

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Gents, I have Lancaster media filters after my chlorine retention tank, and the first is the larger sand filter, for turbidity and pieces of sediment, and the second is the carbon backflush. After a few months I caught a whiff of a mustyish sulphur in the cold line on the washing machine and similar in the fridge. So I shocked the pipes with chlorine and it went away but came back. Upon inspection my backflush (regeneration as the tank top says) was set at 9 days. I moved this to 5 days and the smell went away. My friend says his is set at 7 days on his similar setup. I think my filter media was loading up. I use about 1,000 gallons a week on a 320 foot deep well that pumps 7gpm so I don't worry too much about using lots of water for something like this. It goes to a daylight drain incidentally. I am told I am using 90 or so gals each backflush but that is the plumbing supply house rep and I can't tell if he really knows a lot. Does anyone want to offer me input as to the frequency they see as needed? Iron bacteria is the smell culprit incidentally. The chlorine seems to work nice, and I have considered going to Hyd. perox. But I hate to tamper with success. Am I backflushing too much, too little, is there a guidepost or set of rules the experts use, or is it kind of different for everyone depending on the pie water issues? The refrigerator ice is the place where I'm most interested in making sure the water is sweet. I have a second Carbon filter going to that in the line to kitchen, a ten inch five micron cartridge. That unit makes it easy to shock just that line and of course I got rid of the fridge water filter and installed the bypass plug. No one wants to be swapping a forty dollar filter every month.
 

Reach4

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What is your residual chlorine before your carbon filter? Maybe you need more chlorine. The iron would usually settle out in the contact tank. Do you have a blowdown port on your contact/retention tank to remove the precipitate? If you did, that should clear up most of the stuff before the water ever hits your sand filter. I guess the design in your system is to have all of the solids to read the sand filter. That makes sense.


http://www.lamotte.com/en/water-wastewater/test-strips/2964-g.html free chlorine
would be a low range test strip for free chlorine. I think you would want between 2 and 4 ppm into your GAC tank.

I would consider putting the carbon filter into bypass for a while. Let your plumbing, including the washing machine, get cleaned.

Also, maybe try sanitizing your well and plumbing. You may be able to get IRB and SRB knocked down before your chlorine treatment. That would reduce gunk that your pressure tank and pressure switch have to deal with. https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my sanitizing write-up.
 
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GTOwagon

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What is your residual chlorine before your carbon filter? Maybe you need more chlorine. The iron would usually settle out in the contact tank. Do you have a blowdown port on your contact/retention tank to remove the precipitate? If you did, that should clear up most of the stuff before the water ever hits your sand filter. I guess the design in your system is to have all of the solids to read the sand filter. That makes sense.


http://www.lamotte.com/en/water-wastewater/test-strips/2964-g.html free chlorine
would be a low range test strip for free chlorine. I think you would want between 2 and 4 ppm into your GAC tank.

I would consider putting the carbon filter into bypass for a while. Let your plumbing, including the washing machine, get cleaned.

Also, maybe try sanitizing your well and plumbing. You may be able to get IRB and SRB knocked down before your chlorine treatment. That would reduce gunk that your pressure tank and pressure switch have to deal with. https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my sanitizing write-up.
You know I haven't ever shocked my well. I am scared because I have read so many people warn against putting chlorine into the well casing that might either corrode things or make it worse.i read about these warning all the time so I don't know what to believe. So I sanitize by injecting chlorine just before the pressure tank and the name I have a 120 gallon retention tank. My wife is an organic chemist and she maintains that a second retention tank would also be beneficial. She claims that longer contact with a larger portion of water would make for less chlorine useage and more effectiveness. Better oxidation. Speaking of that she maintains H2O2 would oxidize better but chlorine is a better bactericide.

Any one ever see a system that uses one and then the other? Like a two stage system? Sounds exotic.

I do drain some water off the bottom every two weeks or so. For maybe five seconds. Now I installed a clear hose running into my sump pit leading to daylight drain for this and my regeneration. I can see the dirty water come out when I open the Ball valve at the bottom of the tank. I have another question regarding second possible retention tank... should it be in parallel or series? My wife thinks either but series might make the water in the second (B) tank clearer... less sediment... any thought on that? At this stage the $500 tank is a bit of a luxury, so it seems. Opinions on that?
 

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My wife is an organic chemist and she maintains that a second retention tank would also be beneficial. She claims that longer contact with a larger portion of water would make for less chlorine useage and more effectiveness. Better oxidation. Speaking of that she maintains H2O2 would oxidize better but chlorine is a better bactericide.
Good thinking. See something like this:http://www.wellmate.com/en-US/produ...ersal-retention-tank/ut-quick-connect-series/

Regarding H2O2, there is an advantage to bleach in that it is easier to measure the residual. But H2O2 has the advantages in other way, and the reaction products are better. The cost difference is reportedly significantly less than it used to be.

Sensafe Low Range Peroxide Check https://sensafe.com/visual-tests/?_bc_fsnf=1&Parameter=Peroxide is not too expensive either.

I think chlorine is reported to be a stronger disinfectant. I don't know the reaction if using both. Bleach is a base, but it gets more active if you drop the pH. Peroxide is an acid. Might make a nice combo.

You know I haven't ever shocked my well. I am scared because I have read so many people warn against putting chlorine into the well casing that might either corrode things or make it worse.i read about these warning all the time so I don't know what to believe.
Significant corrosion takes time. Sanitizing is mostly over in 24 hours. So I don't buy that. I am definitely not an authority, but does that no-sanitizing suggestion come from somebody authoritative? Sanitizing wells is generally accepted as far as I know.

I have another question regarding second possible retention tank... should it be in parallel or series?
Series is the only one that makes sense to me.

Back to the sand filter... what are the tank dimensions, and what is your backwash rate? Sand requires a high backwash rate. Not all pumps will be able to keep up.
 

ditttohead

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Sand filter... what is the actual media. It is unlikely to be sand unless you purchased the system in the 60's.

Can you post a couple pictures of your system?
 

GTOwagon

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I apologize for vagueness and using the "sand filter" nomenclature. It is a Lancaster 7-LETST-2B Bronze Line Electronic Water Filter, Time Clock Model, Featuring The LETCV1F Valve. The tank size is 13x48 and it uses A8014 Filter ag (2 bags). The set up in the house goes Chlorine injection to 60/40 pressure tank (44 gallon tank I recall) to 120 gal retention tank with manual bottom drain, which I let loose once a week to ten days for maybe 10 seconds then the water exits out the top of retention tank to the aggregate filter described above, then to a slightly smaller backwash carbon tank (10x44) of the same manufacturer then to the softener of the same make then to service. I think the softener has the Klack valve? I bypass the softener for refrigerator water and kitchen sink spigot cold. I added a 10x2 5 micron carbon cartridge into that bypass line for my drinking water. The only thing visible on the clear housing cartridge filter has been a minute flecks of what looks like charcoal that might have broken loose from my backwash carbon filter. My water tastes excellent and the only outlier has been this past fall when my ice cubes had a bad smell when they melted and my refrigerator water had a minor smell. I couldn't detect this at the sink no matter how hard I tried, anywhere else except a similar musty smell in the washer which is a topload old school called a Speedqueen. Shocking my plumbing solved that's once. The second time it came back, regenerating solved it. So now I am regenerating every five days instead of nine. Also to note, I had a water specialist come over and he tweaked my softener settings, and tested my free chlorine which was under 1ppm coming out of the retention tank. The Chem tech pump doesn't seem to want to pump enough solution into the line, even though it is set at full stroke. My mix I see 2.5/15 gallons Chl to filtered water in my solution tank. I filled it in October and it is halfway full. He recommended and so has the entire universe, that I buy a Stenner 85/17 adjustable model. I ordered it last night. The local plumbing supply house sells the Chemtech and they swear by them, but I can sure see the value of a peristaltic style pump. I digress.

Thoughts?
 

GTOwagon

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FYI, my water is 7.5 ph, 0.0000 iron and 6 grains hard. So we aren't starting with the worst water. I just think I might have iron bacteria which everyone here in the area has (or maybe it is sulphur bacteria misidentified?) and some minute methane as far as I can tell. Nothing crazy but I think that is the bubble I get sometimes that clear up in a glass fast, no sputtering or spitting at the faucet however. I intend to get better testing done if someone can recommend a cheap lab I can send out to. I am always looking to improve, but certainly don't want to go the Culligan route my young neighbors got sucked into in their new homes next door and one over. Both spent better than twelve grand and they sold them F86 systems, large aeration tanks, double retention tanks and RO. I see no signs of colloids in my water and maybe bc I am onlY 320 feet down and they are 500+ feet down they have worse water. I don't know. I am considering shocking the well this spring.
 

Reach4

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It sounds like a really nice system. You want to analyze to see if the sand-like media is being backwashed at a proper rate and that your pump can deliver that rate. If there is a problem with that, there may be a solution.
Iron bacteria is the smell culprit incidentally.
I had not seen people write about an IRB smell, but searching finds references. SRB is associated with an H2S smell.
, 0.0000 iron
Those two don't go together, unless your 0.0000 iron was not your raw water.

I would sanitize your well and hit the plumbing again. Include your softener during part of the sanitizing, but at reduced chlorine levels from what you do the rest of the system. It may seem like a bad thing to do, and the Clack manual I checked does not mention it. The Fleck manuals include references to using chlorine bleach solution during setup. Include your WH and hot pipes in the sanitizing. A full WH will dilute the chlorine you send to it, so take that into account. You should get the high-range chlorine and pH test strips/rolls on order, so that you will have them if a couple of nice days correspond to days you have available.

For the fridge, consider an RO unit fed with softened water. You don't want to run RO water through metal.

Being able to get your residual chlorine up some will be good.
 

GTOwagon

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Stenner pump on the way. Fresh chlorine here from Agway. When weather warms up I will do the well sanitizing prescribed here. Can someone recommend a water test outfit. I saw somewhere here that one of th online outfits folks like is currently closed due to a merger but it seems others mentioned a different tester. Is there one you guys think makes a good report?

Also I know I should certainly test my water before it gets hit with the chlorine in front of the pressure tank. I have a spigot there and intend to sanitize it as the Moravec people suggest. But does anyone also test THEIR TREATED WATER AS WELL? Also I know I have seen test strips for IRB and SRB. Does anyone have a source for those since water tests do not include them in the results?
 

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