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SFR: softener size, resin volume

Posted by AL77 (My Page) on
Sun, Mar 24, 13 at 22:42


i am uncertain about the correct softener size needed.

source: well water. bored at 87', 10+ years old.

condition: iron 4 ppm, this is clear water iron w/o visible particulates. hardness 60 gpg. pH 6.5. total alkalinity 240 ppm. nitrate/nitrite 0 ppm. copper 0 ppm. chlorine 0 ppm. manganese and sulfides are an unknown.
TDS 1001 ppm. measured with DM-1 meter for an RO+DI system setup for another project unrelated to human consumption.

the well will be tested further mid April. we don't drink from it, even though we could.

two people, 1bath, 1 laundry, 1 kitchen w/o dishwasher. a water heater @40 gal. 95% of the time, only one fixture is being used at a time.

30/50 pressure switch @ pressure tank. 3/4" plumbing to existing old culligan softener, and after it until reaching kitchen/bath sinks at 1/2".

an ecowater CWS V, tech tested the water for hardness and iron content. he added to the 60 gpg, 5 gpg for each ppm of iron. bringing it to 80 gpg, then an additional 10 gpg for some reason, i cannot recall. so, at 90 gpg hardness, and 11-12K grains per day, he suggested nothing less than a 40K unit. around $2,400.

after looking around, it seems there is more to the sizing than capacity. the SFR of resin volume correctly matched to capacity is the goal to reach for if looking for efficiency.

if using 6lbs. of salt per cu.foot of much resin should be used?

i understand two things. too much water into a pile of resin, can cause channeling or leaking, and these effects lead to waste.

i don't understand how to figure for the SFR of resin, and meet water conditioning needs.

apologies for the length of this post. i'll ask the ecowater tech more questions. in the meantime it seems like a good idea to ask for help here.

thank you.

This post was edited by AL77 on Thu, Mar 28, 13 at 12:52

Follow-Up Postings:

RE: SFR: softener size, resin volume

i've since discovered, that at the tub w/faucet full open hot/cold. i am getting 5 gallons of water in 116 seconds. 2.59 gpm!, i don't think i'll have a channeling problem.

ferrous iron, is what i have according to the ecowater tech., and the unit he suggests is the 3502r40. at about 1 1/3rd cubic foot resin volume.

over at without knowing the manganese analysis, it puts me at a minimum of 4 cubic foot of resin!

i am thinking i have a pressure problem, alongside sizing a softener.

This post was edited by AL77 on Wed, Mar 27, 13 at 14:50

RE: SFR: softener size, resin volume

Something is wrong with your analysis. Are you absolutely certain your hardness is 60 gpg and not 60 ppm? 60 gpg equates to 1026 ppm TDS, which is higher than your reported TDS, and that is without any other analysis taken into account! Please verify.

Your water has multiple problems which, unfortunately, require multiple solutions.

pH: Your pH is low and should be brought up closer to neutral. This can be easily accomplished with a neutralizer. Unfortunately, this will add hardness to water that is already very hard.

Iron: While 4 ppm iron CAN be treated with a softener, it SHOULD be treated with separate iron removal. Particularly with water as hard as yours, attempting to treat both iron and hardness with just a softener will most likely result in problems. If, however, you choose to do so, you absolutely MUST regenerate your softener with a minimum of 8 lb salt per cubic ft of resin at a minimum. 9 would be better. 6 lb salt per cubic ft is unacceptable with high iron. You will have to sacrifice some salt efficiency or your softener will quickly become an expensive paperweight. Additionally, you would want your softener to regen frequently.

Given those parameters, could go with a 1.5 cuft softener, regenerating every 3 - 4 days. You will use 120 lbs of salt each month. If you remove the iron first, your salt usage would drop to 73 lbs per month.

Channeling: This is most likely to be cause by an oversized softener. If you were to purchase a 4 cuft softener, you would be virtually guaranteeing yourself a channeling problem.

Pressure: Why do you think you have a pressure problem? What are the low/high pressure settings on your well controller?

RE: SFR: softener size, resin volume

hello aliceinwonderland_id,

thank you for responding.

the analysis was performed by the ecowater tech. 60 gpg, was his conclusion. he added 59 drops of something into the test vial of water, looking for a color change and, then rounded up to 60 gpg.

the TDS: i divided 1001 ppm by 17.1, and get 58.53. the meter for TDS may not be accurate. or, i could have misunderstood what the ecowater tech said.

at any rate, it is best to get an independant lab analysis done. it may take a few days.

the pressure problem is an inconvenience, i must admit. however, at 2.59 gpm, with a 15% psi loss created by adding resistance to the system such as a softener, or any other filters, will reduce service flow even more.

the shower head is rated at 2.5 gpm. i've known for 10 ten years we had low water pressure, just came to accept it. i want to change that reality.

30/50 pressure switch. cut-in at 28 psi, and cut-out around 49 psi. this is on a Well-Rite pressure tank, WR 120 OLC. 33 gallon tank. it appears to be functioning as it should.

according to the well construction report: 4/1999. pumping level @ 36'. pumping 40 gpm for 1 hour.

pH correction. separate iron removal system. 1.5cuft.
with current analysis. alright, lemme get a lab analysis.

thank you

This post was edited by AL77 on Tue, Apr 2, 13 at 13:04

updated water analysis, well flow rate


PDC Laboratories, Inc. provided the analysis.

Alkalinity: total as CaCO3, 420 mg/L
Hardness: 980 mg CaCO3/L
pH: 7.51 pH Units
TDS: 1600mg/L
Sulfide: 11 mg/L
Iron: 2.3 mg/L
Manganese: 160 ug/L

the cost for that analysis, was $173.

as for microbiological results, that will be provided by the state lab. yes, cost factors into the decision for using the state lab for microbiological analysis w/ nitrates/nitrites.

the iron number dropped, compared to the ecowater and test strip. no matter, i am going to use a filter before the softener.

the pH, is better...not by much. should i still plan on a neutralizing system before the pressure tank?

budgetwater suggested, w/ the analysis provided in the original post: 1st in-line, chemical feed, 16 gal. 2nd in-line 10" Terminox ISM, and 3rd, 30k demand water softener. they used the updated water flow information which is 13.893 gpm after the pressure tank.

i've been looking at the different mediums suggested for iron removal. probably going the Terminox direction, unless the Pyrolox system can be made to work with my flow rate for backwashing, as Pyrolox has a longer track record.

thanks for any help you may provide.

RE: SFR: softener size, resin volume

All iron removal media is heavy - you just need to ensure you can get adequate flow to backwash the filter. They typically need a backwash every night.

To find out how much flow you can get, open an outdoor spigot completely and time how long it takes to fill a bucket of known volume. Repeat several times and average your numbers. If you only have indoor fixtures, open them all at the same time and get a flow from each and add them up.

If you find that you don't have enough flow rate for a Terminox filter, you may wish to consider aeration followed by filtration. It will take up more space, but won't need as much backwash.

A 1 cubic ft softner (the 30K the vendor is recommending) is too small. However, your water is just so high in hardness, that a softener sized strictly on hardness would be too big for your flow rates. We will have to make a compromise and sacrifice some water efficiency, to keep your softener small enough to prevent channeling [channeling is where water travels through only a small portion of the resin bed and you quickly get hard water].

Additionally, your TDS is high, which presents another challenge. The higher the TDS, the more hardness leakage you will have from your softener. With a more typical TDS, this results in a few ppm of hardness that you would never notice. However, in order to maintain your water below 1 gpg, you will have to regen with 12 lb salt per cubic ft of resin. It's not very salt efficient - you'll use about 100 lb salt per month. If you can live with about 3 gpg hardness, you will use about 70 lb salt per month instead.

Are the other wells in your area this bad? Do your neighbors have the same problems? If so, it is what it is and we deal with it. If not, however, you may wish to consider drilling your well deeper to find better water.

Your water is, frankly, outside the norm that most softener dealers are technically savvy enough to deal with. And the online dealers - no way will they have the expertise. You may wish to consider a company that deals with commercial and light industrial water treatment. Those companies have highly trained personnel and much more expertise.

RE: SFR: softener size, resin volume

hello aliceinwonderland_id.


the original well digger, stated that the water i have at my depth, is typical for this area. then the conversation switched to flow rate, pumps and pressure. for $2100 he can install a constant pressure pump. he claimed it was a demand type pump, that could deliver 60-70 psi at any tap even with two or more opened for as long as they were open. not sure if this is the beginning of a solution to backwashing or just another sales pitch.

the nearest neighbor lives just over 1/4 mile away, and i don't know them. sad but true.

i'll have to accept the facts, and do the best i can to remove iron, and get as close to softwater as i can and live with inefficient salt and water usage. ahh, what the heck, i've been doing that for years, and been too dumb to know it 'til now.

as far as locating a commercial or light-industrial water treatment company goes...not going well.

kinetico does not service the area i live in.

do you think twin tanks would be a good option for my water conditions?

geez, i'll keep looking. thanks again.

RE: SFR: softener size, resin volume

A twin tank system may be a good option for your water. However, flow rate will be key. If you are only capable of 2.59 gpm, you can't have one tank regenerating and still use the other one. Do you have an outdoor spigot from which you can get a flow rate? That will be more indicative of the max flow your system can provide than the bathtub.

Since you have access to the folks that originally drilled your well, get the information on your existing pump. You want to know brand, hp and a pump curve if they have it. If they don't have the pump curve, I can probably find it if you can find out what pump is installed.

flow rates, pump type and kinetico


by-passed the current softener for the following:

outside spigot: 9.1 gpm is the average of 10, 5 gallon timed runs.
tub: 3.0 gpm. w/ pressure tank starting at 50 psi.

laundry hot/cold taps opened: 14 gpm. w/ pressure tank starting at 50 psi.

aside from the jump in gpm...on the cold side, i have black...inky water with black granuals. this stuff stained my fingers as i felt the granuals. wonder if this is due to the fact the cold side does not get used alot and/or being an indicator of manganese. this does not happen from the other taps.

not by-passed results:

outside spigot: 4.7 gpm, w/ pressure tank at 50 psi.
tub: 2.6 gpm, w/ pressure tank at 50 psi.
laundry: 4.7 gpm, w/ pressure tank at 50 psi.

now, after following the directions budgetwater gives for finding flow rate, the yield is 13.89 gpm. it takes 33 seconds to refill the pressure tank, and 7 3/4 gallons to drawn to get the pump to start the refill.

it is clear, the softener is restricted.
it is clear, there is a plumbing problem at the tub, and at the outside spigot. the laundry is better than the outside spigot, yet the furthest away from the pressure tank.

the well pump is a 4" Berkeley submersible 1/2 hp. 7-10 gpm depending upon depth. this is a 12 year old pump, judging by the numbers it is working fine.

i tried one last time to get kinetico to come out, and they will be here today at 11:00 am.

as it stands, if service flow is adequate: a 10" terminox tank 1.5 cu.ft and a 1.5 cu.ft single softener or 2.0 cu.ft twin tank softener seems the work-around for iron, hardness and TDS.

oh, and fix the plumbing.

RE: SFR: softener size, resin volume

Use 9.1 gpm for any calculations. The method budgetwater gave you does a fine job of telling you about your well makeup rate, but a poor job of telling you the flow rate you can expect in your home.

The good news is, your flow rates are fine for Terminox and for a twin tank softener.

RE: SFR: softener size, resin volume


the kinetico rep. used color titration methods for pH 7.2, hardness 65 gpg, iron 2.0 ppm and nitrates not present. the TDS 1360 ppm. there is iron-bacteria present which he says could be maintained with periodic chlorine maintenance through the brine tank. if the unit he suggests removes the iron as well as claimed, the iron bacteria levels do not warrant a system ahead of a softener.

he recommends the S350.

and will add a Canature RO system for no extra cost above the S350. $4330.

given the reputation Kinetico products/service has, my only concern is doing what you said could be done with a softener, but should not. using the softener to remove iron.

weighing the options.

RE: SFR: softener size, resin volume

My preference is not to use just a softener with hardness that high, BUT if they are willing to give you a performance guarantee you should be in good hands with Kinetico.

more thoughts

hello aliceinwonderland_id,

i will use an iron filter before a softener.

Kinetico rep. won't give a performance guarantee of 0 gpg hardness after the softener. does not recommend more expense beyond the S350 for iron filtration concerns.

Ecowater rep. never recommended any iron filtration. he will install one if i want it, a ETF AIV 10" tank, and while he would not discourage me from moving to the next larger softener from the ECR3502R40 to ECR3502R70, i would go to the R70, for piece of mind...unless it is too big for my flow rate, what do you think?

the Ecowater solution is a single tank + iron filtration, price is a little less than the Kinetico.

diy, i could handle...just don't know if i want to.

alright, moving in another direction.

hello @aliceinwonderland_id,

i've decided to move to a constant pressure pump. Grundfos 3/4 hp. 15 gpm at 60 psi.

the tub faucet/valve is a single handle Delta, and the cartridge in it needs to be replaced.

I am going with an 80K single tank Fleck 7000SXT softener, resin type undetermined. Looking at the 10% cross-linked, Purolite C100MBH.

MangOx Iron Filter 1.5 ft3 w/ Fleck 7000SXT.

Kinetico is out. Ecowater is out. Terminox is out. I am in.

RE: SFR: softener size, resin volume

Sounds like a good choice. There is no need to pay the extra for a 10% crosslinked resin since your water doesn't contain oxidizers like city water would. Purolite resin, however, is an excellent choice.

You will need to ensure your MangOx filter backwashes when nothing else is using water as it will take all that you have available.

RE: SFR: softener size, resin volume


ok, gottcha on the 10% crosslinked resin.

the top basket you recommend for softeners, could this be used on the iron filter, if the Vortec distributor allows for it?

are you willing to help me setup the Fleck valves?

i am concerned with the chemical makeup of the remainder of TDS, after substracting the Hardness number.

manganese dioxide, is 80% of the filter in MangOx, would a certain level of ppm of sodium or sulfates interfere with medium longevity?

i sense another lab test headed my way.

RE: SFR: softener size, resin volume

Top basket in the iron filter - Possible to use one but not a critical item because the media is so heavy.

Fleck valve setup - Yes, of course, I'd be happy to help.

MangOx interference - You really shouldn't have an issue with what is in your water, but one possibility is what may NOT be in your water. I recommend an ORP test (oxidation/reduction potential). You want a # 200 or higher for it to work correctly. If your ORP is low, you may need air, chlorine or ozone injection upstream.

RE: SFR: softener size, resin volume

ok, let me see about getting ORP information. it will be 7-10 days before the well pump is switched over anyhow.

3 more test results, and new cp pump


PDC Laboratories, Inc. provided the following analysis...for $76.

Anions - PIA: Sulfate900 mg/L

General Chemistry - PIA: Oxidation Reduction Potential (ORP) 140mV

Total Metals - PIA: Sodium 150mg/L

a big thanks for aliceinwonderland_id !!! your suggestion to test the ORP level, saved me from purchasing something that would not have worked.*****

the minimum ORP level for use with a MangOx system is 170mV.

the constant pressure pump/CU 301 controller...working fine. the outside bib gives 12.5 gpm...should be 15 gpm @ 60 psi...but there is a run of about 3' of glavanized pipe connected directly, through a valve too copper. i am thinking the mini-battery created by that connection is a source of restriction after 13 years. it will be removed.

looks like an air injection, birm iron filter is the direction to head. i'll be back with more later.

follow through


removed the old piping and softener, replaced with 1" copper, headed towards a future iron filter and softener.

now i get 12 gpm @ 50 psi constant, through an outside bib. before the change, it ran 12.5 gpm @ 60 psi. very pleased with fixing the water pressure annoyance.

i've settled on an iron filter using a Fleck 2510 AIO/SXT valve, air charged w/ 80% manganese dioxide. a 2 cu.ft. unit.

aliceinwonderland_id, in the beginning you suggested a 48K softener.

would i be inviting problems by going with a 64K?

beginning to think, i'm over-thinking.

RE: SFR: softener size, resin volume


hmmmm, not sure what i did to earn no further advice. maybe the fella is hurt or on vacation.

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