Help needed inputting Murphy's water report into Bru'n Water

[inthedark]

I've just had a reply from the lab manager - he's looking into the issues I reported and will be getting the equipment manufacturer in next week to look at any potential problems too.

[Matt12398]

My brother had an error in his report as well last year and later after some back and forth they eventually admitted a misreported figure. It does leave you wondering how reliable the results are.

[WallyBrew]

I've just had a reply from the lab manager - he's looking into the issues I reported and will be getting the equipment manufacturer in next week to look at any potential problems too.

If I were running that establishment I would have a standard water prepared and run it through to check the system is working or is that just too obvious or easy?

[Dave S]

I've just had a reply from the lab manager - he's looking into the issues I reported and will be getting the equipment manufacturer in next week to look at any potential problems too.

If I were running that establishment I would have a standard water prepared and run it through to check the system is working or is that just too obvious or easy?

Yes!

[Graham]

If I were running that establishment I would have a standard water prepared and run it through to check the system is working or is that just too obvious or easy?

I would suggest that if the equipment that they use is a reasonably high-tech bit of kit, it will perform a calibration cycle before it does the analyses of the target samples. When I have had water samples tested by a friendly hospital technician the calibration phase has always been shown on the printouts that were returned to me.

I think that the problem, and I have seen this lots of times in water utility report sheets,is when they calculate an ion that they have not measured, from the parameters that have been measured. There have been a number of times when it is obvious that the sodium content has been included in the utility's hardness figure; it doesn't matter to the average householder who only wishes to know how much washing powder to use in his or her machine; so the utility does not take requests from public plebs seriously, or at least they do not believe that accuracy is important. If one has the privilege to get to talk to someone at the utility who knows what he is about, one gets much better answers to the questions.

Historically, there have been several issues raised about the accuracy of data supplied by the company concerned; in my view the data that they supply to their clients should be printed from an internal spreadsheet that would highlight to the technician if something does not look right mathematically. It could save a lot of embarrassment on both sides of the fence.

[SiHoltye]

I have and use a hanna alkalinity tester. It matches the Murphy's findings but takes more than their suggested addition of AMS to reach their suggested target alkalinity. Confidence..low.

[crookedeyeboy]

Can I clarify the situation on here before, as with many internet forum threads, this gets out of hand.

We use a Thermo Fisher Gallery 'Beermaster' discrete automated spectrophotometer to analyse liquor samples for breweries and brewers all over the world.
We have found an issue with a couple of results from after Christmas and have also found where the error lies.

Please be assured this is a very accurate and reliable machine, it should be for the price it costs.

As for running water through it as a QC, it isnt that simple. We have to make our own QC samples up and even with this in place the error still would have not been apparent.

I had a suspicion that some of the alaklinity readings were high but some more testing confirmed that there was an error with the reagents being used. This has now been rectified and we validate all our work against manual EBC methods to ensure both methods are giving the same result.

Ove the next couple of years we are heading for UKAS accreditation in this area, we are already accredited for some of our methods.

I hope this helps to give you all some confidence in continuing to use our valuable service.
Thanks

[inthedark]

OK, Paul has sent me a replacement report with a much lower alkalinity figure, so the numbers are now:

My figures are:
pH 7.16
Nitrate 30
Calcium 115
Magnesium 3
Chloride 24.58
Sulphate 15.79
Alkalinity (as CaCO3) 225

Again, I'm using Na=13.3 from the 2012 water report.

The ion difference has reduced to 6.56 - 5.52 which is better than before but still not balanced. Any ideas about what I should do with these numbers?

Thanks

Paul

[mabrungard]

You do need to include the nitrate value in the summation. It is a major anion in that report. That does close the difference significantly between the cation and anion sums. Your assumption of 13.3 for the Na may be off in this case. If the rest of the ion concentrations are correct, it may be that the sodium is actually lower than assumed. If it has been raining, that might reduce some of that mineralization.

[inthedark]

You do need to include the nitrate value in the summation. It is a major anion in that report. That does close the difference significantly between the cation and anion sums.

Yes, in Bru'n Water that seems to do the trick, there's nowhere to enter nitrate into GW's calculator, so perhaps that explains the larger difference in that model.

Your assumption of 13.3 for the Na may be off in this case. If the rest of the ion concentrations are correct, it may be that the sodium is actually lower than assumed. If it has been raining, that might reduce some of that mineralization.

Yes, it has been raining heavily almost daily for some weeks now, so that makes a lot of sense. Using a guess of 12ppm for Na gets the balance into the ballpark.

Are other ions or alkalinity similarly diluted by heavy rain? Just considering whether it would be prudent to get another report when things dry out?

[Eric]

Got my revised report too, alkalinity 240ppm, which matches my finding. However, my confidence is a bit dented with a different correction factor for yours than mine.

Nitrates will add 0.48meq (NO3 mg/l divided by 62) to the anions total making 6.0.
You have no figure for potassium but that is normally insignificant which in any case would increase imbalance.
A Sodium figure of 13.3 sits well with the other numbers for a UK water. If sodium was absent it would come close to a balance (13.3/23 = 0.58meq) but I can't imagine such a water without it.

I'm puzzled.

[WallyBrew]

Lets try again

If you put all those figures into Bru'n Water you'll get a difference of 0.56, cations of 6.56 and anions of 6.00 (this is from putting 225 in the total alkalinity box and transferring the calculated carbonate and bicarbonate to their respective boxes)

Now go to the "water adjustment page"

Suddenly your cations are 6.6 and anions 5.5 - WHY????

Because it is not interested in your nitrate (or potassium) because they do not appear in any of the BALANCED profiles.

So why bother to put it in the water report input page??

[inthedark]

Got me...

[barneey]

The Alkalinity / Calcium reporting problem isn't a new one, I first mentioned a wrong report back in 2011.

[SiHoltye]

I have and use a hanna alkalinity tester. It matches the Murphy's findings but takes more than their suggested addition of AMS to reach their suggested target alkalinity. Confidence..low.

I'd like to correct my earlier statement. Since agitating my liquor through pump recirculation and doing so for twenty minutes, using my alkalinity tester I have discovered I can use the Murphy's recommended amount of AMS to drop my RA to where they predict.