A few questions first:

1) Is the 70 gallons per day metered or are you estimating? If estimating, it's a bit on the high side - is there a reason for the high estimate?

2) City or well water?

3) What type of test was used to determine hardness?

4) Do you have a complete analysis? If you don't have a complete analysis, get one. You want to know: pH, TDS, hardness, iron, manganese, sulfur compounds, nitrates, alkalinity, bacteria (if on a well), turbidity, particulate

the 70 gallons per day is what i see most companies use to calculate per person usage. I figured my actual over the past year: 320 gallons per day average (320/7=approx. 45 gallons per person) This figure was derived from my actual municipal water billing over the past year. ( I had to convert the cubic readings to gallons)

city water yes

testing done by city water treatment employees and local store that sells softeners. Not sure what type of test is was.

sounds as if if I have no major problems with ph, bacteria, nitrates, iron, etc.

I'm not attempting to be difficult here, but I did not ask for the analysis numbers to amuse myself. You may not have a "major problem" with any of the items, but they will affect proper water softener sizing. I could spout off a size based on what you've provided thus far, but it could be way off, so I won't.

I will see if I can get all the results. Sorry about that. Assuming I have high levels of nitrates or magnesium, or whatever, how would this affect the sizing? (i'm a novice at this) Would it be that the larger sizes will do a better job of removing these? Thanks for help. Will try and get specific details tomorrow.

Nothing to add here but had a question if you don't mind for Alice. Was wondering how (edited quote)" pH, sulfur compounds, nitrates, alkalinity, bacteria (if on a well), turbidity.".have to do with the sizing of softener. Or is this just in case other conditioning is need? From all the reading I've been doing, I've not seen yet where or how that some of these come into the equation.

Don't get me wrong. I don't know anything. Still learning.
Thanks

Here is a link to the pdf of the quality water report where I live.

http://www.windom-mn.com/wp-content/uploads/2012/06/2011-water-quality-report.pdf

In a nutshell:

Magnesium and calcium are the major components of hardness, the first step in softener sizing.

If pH is out of whack too far in either direction, softener performance will be compromised or resin damage will occur.

If TDS is too high, the softener will need to be regenerated with a higher salt dosage than we would normally use for best efficiency. Failure to do so will result in hardness bleed. This changes the recommended softener size.

Each ppm of iron or manganese must be treated as if it were 68 ppm of hardness, drastically increasing the softener size needed. If they are too high, a softener would not be adequate.

Sulfates will foul a softener fairly rapidly. I would be derelict to recommend a softener if it would quit working within a few months.

Nitrates will damage resin.

Bacteria will foul a softener.

We want to know if you are on city water because the chlorine used to keep your water safe will also damage the softener resin. A better grade of resin is necessary.

Turbidity, if high enough, could render a softener useless as well, either fouling or damaging resin, depending upon the reason for the turbidity.

High alkalinity, like high TDS, will cause hardness bleed and possible resin damage so it changes the regen salt dosage, which changes softener size.

Water chemistry is complex and all of the components interact. Specifying water treatment is not as simple as plugging a couple of numbers into an equation - there is a thought process involved.

Yes it is not as simple as going to Home Depot and grabbing a softener. The city water superintendent told me that the magnesium and calcium are filtered at the treatment plant and meet or exceed government standards. Sounds as if they treat these pretty aggressively.

ph 7.2-7.6

iron .02-.03

Not sure if you looked at the link I provide in previous post referring to the city quality water test. Any other information you may need?

tdj32 - The water quality report is missing vital information. Generally, a city will issue a quarterly report with complete analysis. I find it interesting that, though their website specifies that they perform iron and magnesium removal on the well water before distribution, the report includes neither analysis.

You may wish to call them to find the missing information. I still do not have: pH, TDS, iron, manganese, alkalinity. Since you are on city water, turbidity and particulates are not likely problems, unless you have noticeable cloudiness or particles in your water.

Since the city water report does not indicate hardness, I will assume your local water pro did the test. If s/he is anything like 99% of the softener salespeople out there, the results are likely inaccurate. You should find a local certified lab (the folks at the city treatment plant can probably help you) and get a sample of your water tested. You have a lot of people in your house and will need a fairly large softener - we need to get this right so you don't waste your money.

I must have been typing while you posted.

Your hardness, if 25 is accurate, is still quite high. Meeting government standards for calcium and magnesium basically means that the water doesn't contain enough to be cement so will actually flow.

"Magnesium and calcium are the major components of hardness, the first step in softener sizing"

"Each ppm of iron or manganese must be treated as if it were 68 ppm of hardness... "

IIRC magnesium and manganese occupy two places on the periodic table as different elements.

Are they interchangeable in water treatment?

Here is the latest from the city water superintendent.

ph- 7.2-7.6
iron- .08
manganese- .03
alkalinity- filtered 294mg/l
TDS-456-470 mg/l ( I think he also divided these 2 figures by 17.2 and got 27 and 26.5 respectively)

I hope I got this right. I was jotting down figures over the phone.

lurker - I'm unsure what point you are trying to make.

tdj32 - At your current usage rate of 45 gpd/person, a 3.5 cubic ft softener will work for you. However, if there are currently young children in the house they will use more water as they become teens. At a more typical 60 gpd/person you would need a 4.0 cubic ft softener. I would go with the 4.0, unless you have a couple of kids that will be leaving home soon. You will need to make that decision based on what you think your water usage will look like over the next several years.

You absolutely must have:

1. High-quality resin, preferably American-made for even size distribution. This becomes more important in a larger softer to avoid channeling.

2. 10% cross-linked resin. You are on city water and the additional cross-linking will allow the resin to withstand the chlorine in the water.

3. Top distribution basket

4. Gravel underbed

5. Fleck or equivalent valve

6. Noryl bypass

Backwash: THIS IS IMPORTANT: You will need 9 gpm to backwash a 3.5 cu ft softener and 10 gpm for a 4.0 cu ft softener. If you cannot get that flow rate [measure to be absolutely certain], you will need to get a twin-tank softener instead (this would be be two smaller softener tanks with one controller).

Once you have a softener on site, I can help you with programming for efficient operation. Please just add to this thread at the time so all information stays in one place.

I still urge you to get a test of the water at your house. If the water picks up anything, particularly iron, on its way to your home, it will change softener operation.

This post was edited by aliceinwonderland_id on Wed, Feb 20, 13 at 13:57

My question was pretty simple...

Is manganese a factor in the compensated hardness calculation or is magnesium a factor in the compensated hardness calculation?

In your post above you use those two different elements interchangeably.

How do i measure flow rate? Also a 80,000 grain softener is 2.5 and the 96,000 is 3.0 cubic ft and 110,000 is 3.5 cu ft. By my calculations which may not be right, all 3 would handle my current water usage. How in the world would you figure out which one is the most efficient? One would regenerate more often than the others but the other ones would use more salt and water per regeneration correct? Also, the less regenerations should mean more valve life. Am I correct? How would I figure salt and water usage for each? Is efficiency the main reason for suggesting the 3.5 or 4.0 cu ft softener? Also I have 3/4 inch plumbing. Will this work with a large softener like 3.5 or 4.0? I could not find a 4 cu ft. softener and most sites offer the 8% cross-linked resin but offer others like fine mesh, some have a name with 80k after them. Confused a little on the resin options available. Also my water usage would be relatively stable with older kids graduating while younger ones coming into the teens. Thanks a ton for your help!

Alright, softener 101.

First, you want a softener to regenerate every seven days. If you fail to regen often enough, the resin bed becomes compacted and beads get crushed. Then one of two things happen. Either the crushed beads get washed out during backwash and the bed reduces in volume over time, OR the re are too many crushed beads and they cannot be removed during backwash and you get channeling. Either way, you get hard water.

When a 3.0 softener is listed with a 96,000 grain capacity, that is maximum capacity. In order to actually achieve maximum capacity, you would need to regenerate with 24 lb salt (or more, depending upon the resin) per cubic ft of resin. As you use less salt per regen, the effective capacity of the resin is reduced.

There is a sweet spot between water efficiency (regen less often) and salt efficiency (use less salt per regen). That happens at 6 lb salt per cubic ft of resin, so that is what we aim for. At that salt dosage, a 3 cuft softener has a capacity of about 67,500 grains. From that, we take of 15%, bringing us down to 57,375. We do this to provide a safety factor. We generally set a softener to regenerate in the middle of the night when you are unlikely to be using water. If we fail to set a safety factor, you could run our of soft water. A 3.0 cuft softener would regen every seven days only if you never use more that 45 gpd/person. Two minutes longer in the shower and you're down to six days.

Your 3/4" plumbing will be fine. Note that I specified a top distribution basket.

Cross-linking is different from mesh size. Fine mesh resin has smaller beads and is appropriate if you have iron. Cross-linking is basically linking together of plastic molecules on the molecular level. More links = stronger chemical resistance. 10% cross-linking is what you want when you have chlorine in your water. It will be more expensive than 6 or 8% cross-linked resin.

This post was edited by aliceinwonderland_id on Wed, Feb 20, 13 at 15:48

lurker - You misunderstood.

The first analysis step in sizing a softener, as you well know, is hardness. Hardness is primarily composed of calcium and magnesium. I was simply explaining the major components of hardness, nothing else.

Second, look at iron and manganese. These are not part of the hardness analysis, but will be removed by softener resin and each ppm of iron and manganese must be treated as if it were 68 ppm of hardness for sizing purposes.

I was not using magnesium and manganese interchangeably.

tdj32 - I just realized I neglected to answer your question about measuring flow rate. You want to find a spigot as close to the location where you will install your softener as possible. Time how long it takes to fill a 5 gallon bucket with the spigot fully open. We can calculate gallons per minute from that information. If you only have a smaller bucket, do the same thing, but repeat it several times and average the times.

i have right around 6gpm flow. tested 3 times at both the bathtub upstairs and a older larger wash sink downstairs where the softener will be located. Not near as high at kitchen sink or bathroom sink.

That is not good news. Let's see if your system is capable of more. Turn on all three at the same time and measure each one and add them up.

If the number is still low, you will have no choice but to get a twin tank softener. Backwash flow rate is vital to softener operation.

I just looked up the 3.5 cu ft softener and the listed backwash flow rate is 4gpm but you stated I needed 9gpm for a 3.5 cu ft softener. Still confused. I measured my flow rates again and came up with these numbers. Tested all of these seperately meaning I only had 1 fixture turned on. I must have made a mistake when I was coming up with 6 gpm.

kitchen faucet=2gpm
main bathroom: faucet=1.2gpm
main bathroom:shower=1.6gpm
main bathroom: tub=4gpm
small bathroom: sink faucet=2.7
downstairs shower: 1.7gpm
downstairs sink: 4gpm (this sink is rarely used. only for cleaning paint brushes and rollers mainly)

I assume you are looking at OPW. They tend to choose a DLFC (drain line flow control) that is undersized for their tanks.

If your water were on the very cold side, with some resins 4 gpm is not out of the question. However, you are on city water and still want to use your softener in the Summer. We can't size for the best case - we have to size for the worst case.

The reason I asked you to measure with several things running at the same time is to determine whether your pipes will allow the flow you need. Measuring with only one fixture turned on will not accomplish what we need.

Ok. here is what I got.

Bathroom tub: took 25 seconds to fill 1 gallon bucket
downstairs wash sink: 27 seconds to fill 1 gallon bucket
kitchen faucet: 78 seconds to fill 1 gallon bucket

all 3 fixtures on at once

Here you have the specifications for each water hardness http://www.aquagenesisusa.com/prices-a-ordering.html
hope it help you!

If I were you, I would opt for a twin tank softener, each tank 2.0 cubic feet. Your available flow is just too low to reliably backwash a larger softener and you will run into problems.

This post was edited by aliceinwonderland_id on Fri, Mar 1, 13 at 14:38