First time brewing with RO and Bru'n, what went wrong?

[DonGavlar]

Hi guys,

Would be great if someone could help me dial in what exactly went wrong so that I can amend it for next time.

So today was my first time building my own water profile.

• Seeing as I'm using 100% RO water I skipped the first tab (water profile)
• I also left the second tab as the defaults (Sparge Acidification)
• I input my exact grain bill into the Grain Bill tab including the actual SRM.
• I then selected the Yellow Balanced profile and matched the numbers best I could. I selected 100% dilution with RO water and my Mash/Sparge/Total Batch volumes.
• My pH was still a little high so I went back and added 4oz of acid malt to the bill.
• I was then given a estimate mash pH of 5.38 which I was happy with so went ahead with the brew.
• It told me to add 1.4g Gyps, 1.9g calcium chloride and 1.4g Epsom to the mash. So I heated my mash water, added the salts, mixed them to dissolve fully and then added the water to the mash, gave it a thorough stir and then took samples at both 10 and 30 mins.
• Both samples gave me a pH of 5.6, quite a bit off 5.38.
• I carried on and then added the amount it told me to the sparge water, sparged and went on with the boil.

Now I know many many people use this software and rave about how great it is. So I'm certain that me missing my mash pH is my own doing and not the software getting it wrong.

• My pH meter is brand new, not a cheap one and been calibrated by 3 points.
• I have supposedly high accuracy scales, they measure to 0.01 of a gram. So I don't think I added the wrong amounts of salts.
• I definitely added 4oz of acid malt and also double checked over my grain bill.

So, what did I do wrong? I must of made a mistake somewhere along the way but no idea where. This is my first time using Bru'n water so I'm guessing I made a mistake in the software itself.

Thanks

 

[FVillatoro]

Heya,

Did you cool the wort sample and brought it down to the temperature that you calibrated your meter at?

 

[DonGavlar]

Heya,

Did you cool the wort sample and brought it down to the temperature that you calibrated your meter at?

My pH reader supposedly has auto temperature correction but yes to be safe, I cooled the samples to near room temp.

 

[FunkedOut]

Is it possible your RO water profile does not match the profile in the spreadsheet?
Maybe the RO filter system is not filtering as good as it should.

 

[FVillatoro]

My pH reader supposedly has auto temperature correction but yes to be safe, I cooled the samples to near room temp.

Sounds like you did that part correctly then.
From experience, beers such as Pilsners and light blond ales that don't have much crystal malt I've had to add up to 6ml of lactic acid to the mash to bring it down to 5.2-5.3 mash PH.
And dark beers such as stouts tend to be much lower than the predicted calculated PH so I usually have to overshoot the predicted mash PH by up to a whole point sometimes with pickling lime.

There's a learning curve to the calculator (at least in my experience), and you need to brew a few batches to get it down.
Also, I've read that if an RO system is new it takes several gallons of water to really start purifying and get that near-distilled clean water.

You may also easily bring down the mash PH by adding some lactic acid and stirring well and checking MASH PH about 10 minutes later - be aware that you will cause some heat loss to the mash.

 

[DonGavlar]

Is it possible your RO water profile does not match the profile in the spreadsheet?
Maybe the RO filter system is not filtering as good as it should.

I don't have an actual profile for the RO water I use, however, I get it from an aquarium shop which has a huge RO system and the shop has quite a good reputation. I'll definitely ask them for a report on it though.

Sounds like you did that part correctly then.
From experience, beers such as Pilsners and light blond ales that don't have much crystal malt I've had to add up to 6ml of lactic acid to the mash to bring it down to 5.2-5.3 mash PH.
And dark beers such as stouts tend to be much lower than the predicted calculated PH so I usually have to overshoot the predicted mash PH by up to a whole point sometimes with pickling lime.

There's a learning curve to the calculator (at least in my experience), and you need to brew a few batches to get it down.
Also, I've read that if an RO system is new it takes several gallons of water to really start purifying and get that near-distilled clean water.

You may also easily bring down the mash PH by adding some lactic acid and stirring well and checking MASH PH about 10 minutes later - be aware that you will cause some heat loss to the mash.

Ah, well I was actually brewing a witbier with no crystal in it, so perhaps thats why? But would the software really be off by 0.2/0.3 points?

 

[bigtex52]

Just a thought. Did the aquarium store sell you RODI water. The deionizing part maybe screwing things up. You probably need R O only.

 

[DonGavlar]

Just a thought. Did the aquarium store sell you RODI water. The deionizing part maybe screwing things up. You probably need R O only.

I think they sell it as just RO water, however, I have no idea you may well be right with that. I will ask them if it is RODI when i go back.

 

[bigtex52]

I used to make my own for a home saltwater reef aquarium with a large RO water filter and DI unit . The RO water also branched off to a pure water holding tank at the kitchen sink and was great tasting. I tried drinking some DI water one time that I had extra of and it was nasty!! Flat and astringent. I later discovered that it isn't healthy to drink since it is so devoid of minerals and screwed up ionicly. It can actually strip minerals out of your body because of the ionic charges/lack of charges.

 

[DonGavlar]

I used to make my own for a home saltwater reef aquarium with a large RO water filter and DI unit . The RO water also branched off to a pure water holding tank at the kitchen sink and was great tasting. I tried drinking some DI water one time that I had extra of and it was nasty!! Flat and astringent. I later discovered that it isn't healthy to drink since it is so devoid of minerals and screwed up ionicly. It can actually strip minerals out of your body because of the ionic charges/lack of charges.

Yeah that doesn’t sound good, I hope I haven’t just made a batch with that! Ill have to ring and ask.

 

[bigtex52]

Hope it works out for you!

 

[FunkedOut]

I am by no means an expert on water chemistry...
If everything else is in order, and your mash is higher in ph than predicted, I would think your water has more alkalinity than modeled, not less.
I doubt your water profile is softer than listed in the spreadsheet.
Plus you added minerals, so your water is not devoid of them.

 

[kylevester]

DI water is even more pure than RO water. True DI water is devoid of minerals and will have a lower pH. The RO water you typically get in the store will not be that pure, but should be very much like distilled water. Something like less than 10 ppm of TDS is expected.

However, there are many flavors of RO membranes and salt rejection. The RO you got your water from may not be as high quality as what Brun Water assumes for RO water. That and an error inputting on Brun Water are the most likely culprits.

 

[BlueHouseBrewhaus]

A pH swing of 0.2 is not that big and shouldn't effect the brew. There may be slight variations in the minimal minerals present in RO water depending on where it came from (i.e. home filter vs Walmart). However, the more significant variable is going to be the grains. U.S. 2-row pale malt may yield different mash pH depending on whether it's Dingeman vs Fawcett vs Weyermann. You can post this question in the Brew Science forum but I suspect Martin (who hangs out there and created Bru'nwater) will give you a similar answer. Either way, I wouldn't sweat it. My pH regularly comes in about 0.1 higher than predicted so I just take it into account.

 

[Buckeye_Hydro]

Something like less than 10 ppm of TDS is expected.

One of the important spec's of an RO membrane is called "rejection rate." Rejection is specified as a percentage - meaning what percent of the TDS in the feedwater will the membrane NOT allow through to the purified water. Rejection rates on membranes from different manufacturer's vary, but they are typically between 90% and 99%.

So rather than aiming for a TDS reading of "something less than 10" ppm in your RO water, check the % rejection. One of the symptoms of an RO membrane gone bad is a poor rejection rate (e.g., 80%). Even with a membrane that is functioning perfectly, the higher the TDS of your feedwater, the higher the TDS of your RO water will be.

Russ

 

[myndflyte]

Was in the same boat this past weekend as you OP. I was brewing a hefe using DI water and used Bru'n water to calculate my mineral additions. The program said I should have a pH of 5.34 but my actual pH came in at 5.50 after 30 min. I figured this was good enough and didn't mess with things.

It sounds like based on the style, you have to adjust a little bit i.e. shoot for a lower pH with light beers and a slightly higher pH with dark beers.]

EDIT: I'll also mention I added acid malt as well and I'm thinking that might also play a role in missing my pH. I'm guessing that the amount of lactic acid on acid malt may not always be consistent. But that's just my 2 cents.

 

[DonGavlar]

Was in the same boat this past weekend as you OP. I was brewing a hefe using DI water and used Bru'n water to calculate my mineral additions. The program said I should have a pH of 5.34 but my actual pH came in at 5.50 after 30 min. I figured this was good enough and didn't mess with things.

It sounds like based on the style, you have to adjust a little bit i.e. shoot for a lower pH with light beers and a slightly higher pH with dark beers.]

EDIT: I'll also mention I added acid malt as well and I'm thinking that might also play a role in missing my pH. I'm guessing that the amount of lactic acid on acid malt may not always be consistent. But that's just my 2 cents.

Ah right, well that promising that it may not be an error I've made then. My next batch is going to be a pale ale with a fair few crystal malts. I'll have to see if the predicted pH is a little closer this time as someone earlier mentioned the estimate can be a bit off with wheat.

I'll have to grab some lactic acid for my next brew then in case I do need to bring it down some more.

 

[ejf063]

I’ve heard mixed reviews on acid malt so I switched to lactic or phosphoric acid. It’s much more accurate.
Also, I will use water calculators by bru n water, brewers friend and ez water simply to see the variants between each software. Don’t forget, these are calculators that provide estimated results.
In order to amend your procedure, I would keep a bottle of acid on hand. If you have a higher than expected ph, adjust the software to what the ph is of your mash, and figure what your acid addition should be. Also..... just in case..... keep some baking soda near by too.
Brew on!!