Stains in glass carboy even after PBW

[Sol_Om_On]

I just received an old and pretty clean glass carboy from my grandfather who did some brewing some decades past. The only thing problematic is some white stain at the bottom which seems hard to remove. First I tried a mixture of rice, baking soda and water (read that one on another forum). That didn't work so I bought and used some PBW, put about 1 oz of it and filled the 2,5 gallon carboy to the brim. I let it do its magic for 30 minutes then rinsed, but no apparent effect after drying. I have also tried to brush it as well as I could.
I followed the PBW instructions from the site where I bought it. Should I use more or let it sit longer?

Picture below. Thanks for the help!

 

[number40fan]

Are you sure that it is on the inside and not just scratched glass on the outside?

Might give a little vinegar a try if it is in fact on the inside.

 

[Kevin79]

+1 on the vinegar. Also try a PBW soak over night instead of just 30 mins.

 

[flars]

Try a strong PBW solution soak for 24 hours. May be carbonate deposits from hard water or beer stone. Will also take some heavy duty brushing with the PBW in the carboy. Leave the solution in the carboy for a second day if one day doesn't loosen it.

 

[harleybug88]

I would use bleach, diluted with some water. then let it soak for a day or two.

 

[Temptd2]

I've had really good luck getting hard water deposits off things with citric acid. I buy the food-grade stuff on Amazon or eBay. Pour in enough water to cover the offending stain, add about 1/4 cup citric acid, swirl to mix, and let it sit at least overnight.

Now, I have NOT tried this on a glass carboy because we don't use them - but I HAVE used it to get nasty stains off glass bakeware and I also use it in the toilet bowls - it's amazing what it will dissolve! One of our older toilets had really ugly hard water deposits that had been there since we bought this house and NOTHING would remove them - til I tried the citric acid.

Give it a try!

 

[OHIOSTEVE]

OK.. some folks are gonna flip over this advice..... I have done this on several occasions.. it works INSTANTLY and well.. go to the store and buy a product called THE WORKS.. it is an acid hard water stain remover.. squirt a small amount into the carboy and rollit around so the acid touches every stained spot....it will get EVERYTHING off......dump the cleaner then rinse nd rinse and rinse some more.... I got a large amount of carboys that were stained.. this is the only thing that worked and I tried about everything... and yes I have made a BUNCH of beers in em afterwards with zero issues...

 

[Roadie]

As others have said try a strong PBW mix in HOT water and leave it sit overnight.

 

[Sol_Om_On]

Thank you all for your replies! Perhaps I should have specified in the photo that the strong white color is actually a towel underneath the carboy so the stains are the more grey-ish ones They are on the inside of the carboy, of that I'm sure of.

I will try a longer PBW soak as my first solution, but I read on the site where I bought it that longer contact than a few hours could be detrimental to the equipment. Perhaps not so much glass equipment, I don't know. Have you people had any problem with soaking in PBW too long?

 

[Sol_Om_On]

Another question: how strong do you make the PBW mixture?

 

[HBngNOK]

IMO, as others have indicated, it's more than likely mineral build up left over from hard water evaporation. Pour some vinegar in and let it soak overnight.

 

[ArcaneXor]

StarSan might work as well.

 

[Roadie]

Thank you all for your replies! Perhaps I should have specified in the photo that the strong white color is actually a towel underneath the carboy so the stains are the more grey-ish ones They are on the inside of the carboy, of that I'm sure of.

I will try a longer PBW soak as my first solution, but I read on the site where I bought it that longer contact than a few hours could be detrimental to the equipment. Perhaps not so much glass equipment, I don't know. Have you people had any problem with soaking in PBW too long?

PBW isn't going to hurt your glass carboys due to a long soak. I soak at least overnight and never had an issue. Try 1 oz per gallon in the hottest tap water you have and let it sit 24 hours.

 

[TallDan]

I will try a longer PBW soak as my first solution, but I read on the site where I bought it that longer contact than a few hours could be detrimental to the equipment. Perhaps not so much glass equipment, I don't know. Have you people had any problem with soaking in PBW too long?

I left a couple pyrex flasks to soak in PBW and forgot them for a few days. When i got back to them, i had some deposits in a ring on the glass where some water had evaporated off. Initially i thought they were actually damage to the glass and emailed five star about it, but then figured out that it was just some very stubborn deposits. The solution? More PBW! Five Star also suggested StarSan as the acid in it would clean up the PBW deposit.

 

[BreezyBrew]

I left a couple pyrex flasks to soak in PBW and forgot them for a few days. When i got back to them, i had some deposits in a ring on the glass where some water had evaporated off. Initially i thought they were actually damage to the glass and emailed five star about it, but then figured out that it was just some very stubborn deposits. The solution? More PBW! Five Star also suggested StarSan as the acid in it would clean up the PBW deposit.

You can also use vinegar as a cheap alternative. Just make sure you rinse thoroughly!

 

[stu4stew]

Barrel cleaner. Period. That stuff works miracles

 

[NiwotBrew]

Read the threads and look at the pictures of broken glass carboys, invest in some better bottles or SS


Sent from my iPhone using Home Brew

 

[Gar]

OK.. some folks are gonna flip over this advice..... I have done this on several occasions.. it works INSTANTLY and well.. go to the store and buy a product called THE WORKS.. it is an acid hard water stain remover.. squirt a small amount into the carboy and rollit around so the acid touches every stained spot....it will get EVERYTHING off......dump the cleaner then rinse nd rinse and rinse some more.... I got a large amount of carboys that were stained.. this is the only thing that worked and I tried about everything... and yes I have made a BUNCH of beers in em afterwards with zero issues...

The works is amazing i use it for a part of my business that it was not intended for it was a moment of desperation and its the only thing ive ever found that works. other name brands are inferior. never used it as a carboy cleaner tho.

 

[So Shay]

Thank you all for your replies! Perhaps I should have specified in the photo that the strong white color is actually a towel underneath the carboy so the stains are the more grey-ish ones They are on the inside of the carboy, of that I'm sure of.

I will try a longer PBW soak as my first solution, but I read on the site where I bought it that longer contact than a few hours could be detrimental to the equipment. Perhaps not so much glass equipment, I don't know. Have you people had any problem with soaking in PBW too long?

I had two glass carboys soaking for over a week and had some kind of crystal build up on the glass. It seemed to happen near the parts that were closer to air contact. It was onlthe outside of a gallon carboy which I scrubbed off but I haven't been able to completely clean off the inside shoulder of the 3 gallon carboy.

 

[MaxStout]

I had two glass carboys soaking for over a week and had some kind of crystal build up on the glass. It seemed to happen near the parts that were closer to air contact. It was onlthe outside of a gallon carboy which I scrubbed off but I haven't been able to completely clean off the inside shoulder of the 3 gallon carboy.

What did you use to soak them? Just water, or did you add something?

 

[So Shay]

Pbw & hot water

 

[XPLSV]

The Works has fell victim to government regulation: the previous 20% formula has now been downgraded to 9.5%; perhaps it will work as well if you soak longer? I haven't tried it, but came across the notation about the downgrade. Kind of like the Groundclear or Roundup: it has some potentially dangerous stuff in it, so the government downgraded the allowable consumer strength (end result, the current stuff I buy no longer kills the weeds).