Iron in Raw Well Water vs. Water Softener -- Lesser of 2 evils: Sodium or Iron

[jessup]

Well looks like I have a water dilemma. I have well water high in Iron, but low in every other parameter. Raw water = 2.3 ppm Iron which is about 7+ times the EPA recommended limit and well above what you want to use for brewing. Post water softener the Iron is eliminated, but of course it adds Sodium (Na) @ ~ 30 ppm (which is actually relatively low overall).

I've been using the raw water with the Iron and when I'm at about strike temperature the water becomes greenish and discolored and precipitates out the good 'ol green and red rusty looking crap on the bottom of my kettle. I use a 5 micron sediment filter and carbon and it does nothing. I use PBW and Barkeepers Friend between every brew and it keeps happening, ughhhh. BTW the beers with high Iron levels are actually not bad tasting at all!!


I'm thinking about using the softened water since it will eliminate the Iron and just deal with the 30 ppm Sodium since it's reasonable. Unfortunately the softener removes goodies like my Calcium and Chloride, and it surprisingly raises my Sulfate levels from 4 ppm to 30 ppm. I will have to accommodate these changes but at least the Iron is gone.

After hearing the facts, does anyone want to convince me why I shouldn't use water from my water softener??

 

[GilaMinumBeer]

Have you considered using the potassium pellet variants?

 

[jessup]

At six times the cost....no!!! That's a lot of moola. It is a very good suggestion, though, and I really appreciate the feedback. I must admit I did not know the KCl was an option for softeners.

 

[GilaMinumBeer]

At six times the cost....no!!! That's a lot of moola. It is a very good suggestion, though, and I really appreciate the feedback. I must admit I did not know the KCl was an option for softeners.

Yes, the cost is a steep difference. One that I too am struggling with.

My softener will have to drain directly to the exterior of my house. And thus I am concerned about salt saturation killing grass. KCl is a viable solution, but, so is brown grass.

 

[mabrungard]

I take it there wasn't much Ca or Mg in that water since the resulting Na content is actually very modest. If its only in the 30 ppm range, it will be fine. You can go much higher with Na for many beer styles. Just keep it at that level if you are going to boost the SO4 significantly higher.

This is a case where ion-exchange softening does more good than harm with respect to brewing use. There is no need to use potassium chloride in the softener.

 

[ajdelange]

Well looks like I have a water dilemma. I have well water high in Iron, but low in every other parameter. Raw water = 2.3 ppm Iron which is about 7+ times the EPA recommended limit and well above what you want to use for brewing. Post water softener the Iron is eliminated, but of course it adds Sodium (Na) @ ~ 30 ppm (which is actually relatively low overall).

To what level. For brewing it is usually suggested that it be below 0.1 mg/L (which is 1/3 the SMCL).

I've been using the raw water with the Iron and when I'm at about strike temperature the water becomes greenish and discolored and precipitates out the good 'ol green and red rusty looking crap on the bottom of my kettle.

That means that some is coming out and won't appear in the beer.

I use a 5 micron sediment filter and carbon and it does nothing.

That means you have Fe(II), 'clearwater iron' which is soluble. If you can oxidize it to Fe(III) before it goes through the filter then the filter will get it but will probably gum up fast. For small quantities some people aerate thoroughly to oxidize to Fe(III) and then filter through a bed of clean play sand. The sand can be washed and used again.

I'm thinking about using the softened water since it will eliminate the Iron and just deal with the 30 ppm Sodium since it's reasonable.

Since that iron level (assuming it's all clearwater) would only account for about 2 ppm sodium you water must be pretty soft (total hardness of around 60). It's hard to justify a softener for that level of hardness. Perhaps you should look a iron reducing units which do not otherwise soften and will not introduce sodium.

Unfortunately the softener removes goodies like my Calcium and Chloride, and it surprisingly raises my Sulfate levels from 4 ppm to 30 ppm.

Something definitely amiss here. A cation exchange softener such as is usually found in homes will not remove anions such as chloride or sulfate. It will not increase them either. When the resin is exhausted the sodium ions are replaced by treating the beads with brine (NaCl). At the conclusion of treatment there may be a little residual brine left in the bed from incomplete rinse so that Cl- will initially be elevated but that is soon rinsed away by the process water. There is no way one of these units can increase sulfate.

After hearing the facts, does anyone want to convince me why I shouldn't use water from my water softener??

The first thing you need to do is get solid information on the mineral profiles in and out of the softener as you are reporting some things that aren't kosher. The main difference you should see is that calcium and magnesium are way down (to around 1 ppm as CaCO3 each) and that sodium is up by an equivalent amount (each 20 mg/L Ca removed is replace by 23 mg sodium; each 12.15 mg/L Mg removed is replaced by 23 mg sodium).

If the sodium is indeed only 30 mg/L and the iron is down far enough I'd say just use the water as is. Thirty mg/L isn't that much sodium. You won't have quite the flexibility to use NaCl as a chloride source that you would with lower sodium but that shouldn't be a problem in the vast majority of cases.

You will also need to replace the calcium and magnesium (if you really want it).

Using KCl instead of NaCl to recharge does nothing but give you lots of potassium ions instead of sodium ions. Not sure which is 'worse'. Guess in this case it's probably a wash.

 

[jessup]

Thanks for chiming in. Yes some of the facts are def strange. I just bought the house and had the County test the water which ended up being post treatment. After having my iron related issues I analyzed the raw water which is what led to this thread.

To hit some of your points:
-Iron post treatment is below the MDL = <.1 ppm
-Correct that some is precipitating out but I have no clue as to what extent. I'd rather remove the issue confidently.
-I've been reading up on the ways to remove the Iron but since I do 25 gallon batches I'm staying away from getting too complicated. KISS method and staying away from anything that might be a PITA
-All my results were extremely low so yes my water is extremely soft. The only thing even relatively elevated was the dang Iron. I will definitely look into an Iron reducing filter, but since I just bought the house in December I'm stuck with what is already present. At least our whites are staying white unlike some of our neighbors.
-The higher Sulfate was very weird. While it doesn't make sense, that is what the water report said. I was confused as to how everything post treatment was found below the MDL except Sulfate (and Sodium obviously). I wonder how good the County data was since water from a water softener *should* contain more than 30 ppm Na.

I'm gonna give it a go with the softened water and see how things go.

 

[jessup]

Pretreatment (but after 2 stage sediment filter and carbon filter)
pH 7.5
TDS 70
EC .12
Cations .9
Anions 1.1
Sodium 3
Potassium 4
Calcium 9
Magnesium 2
Total Hardness 31
Nitrate <.1
Sulfate 4
Chloride 2
Carbonate <1.0
Bicarbonate 51
Total Alkalinity 42
Total Phosphorus .01
Total Iron 2.16 (I was a little off with my stated value while @ work)

Post Treatment:
pH 7.5
Sodium 27
Sulfate 13 (again my memory was incorrect while posting @ work)
Total Alkalinity 38
*all other values found below the minimum detection limit (MDL)

 

[ajdelange]

In the first test the cations/anions are 0.92/0.97. In the second they are 1.17/1.54 thus the the water softener has added 0.3 mEq/L cations and 0.5 mEq/L anions if this report is to be believed. So I'd ignore that and go with the observation that the sodium post softener is not, in general, objectionable and the alkalinity is pretty nice, supplement the calcium, chloride and sulfate and proceed. Probably a good idea to verify that the softener is indeed taking out the iron though.