Carboy won't come clean

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

mattmcl

Supporting Member
HBT Supporter
Joined
Oct 24, 2008
Messages
725
Reaction score
14
Location
Erie, CO
Someone gave me a 7 gallon carboy, and it's got some dried stains in it, like liquid dripped down the inside and dried there. For the life of me I can't get it clean. Here is what I tried:

Soak for four days with bleach at .25 cup per gallon- no change.

Soak for four days with Star San at 1 oz. per 5 gallons- slight improvement, and the Star San got really cloudy.

Soak for two days with Oxiclean at 1 scoop per gallon- slight improvement.

(I rinsed very well between steps too).

Any ideas? The cloudy Star San leads me to think it's mineral deposits of some kind, but I'm not sure. The carboy has definitely been used to brew as it has gallon markings and a fermometer, but I have no idea what was in it previously.
 
Unless you are certain that the bucket was properly taken care of and cleaned by the previous owner, then I would be hesitant to use it. Small scratches from cleaning it will harbor nasties, thus making bad beer. If you're sure you have a good bucket, I'd say you're good to go after you rinse it a few more times to get ALL the bleach out. Stain or not.

You could use a sponge with hot water and dish detergent.(the handwashing kind)
 
I had the same thing with some I got used. I used an acid rinse I had and it removed it. your starsan is an acid too. If your in no hurry I'd just keep letting the starsan sit in it until it comes clean.
 
You could always up the starsan dosage to make it more acidic. maybe 2oz/5gal then after the soak, add another 5 gallons so its back to norman no rinse sanitizer concentration.
 
PBW will take care of just about any stains or buildup. Bleach and starsan aren't cleaners, so they shouldn't really do much of anything. Yeah, the acid blend will take a little bit off, but you really need something like PBW. A 2 or 3-day soak with some scrubbing via a carboy brush and it'll be like new. I mean, damn, it's glass...you've gotta try really hard to actually "stain" glass.
 
Yeah, that's what I thought! I've scrubbed too, and I just can't get enough leverage. Isn't PBW an oxygen cleaner, like Oxiclean?

Yes it is. It works best on organic soilage. You are probably correct in thinking it is mineral deposits as that is what Star San will "clean" and that is what makes it cloudy. I'd try using more of it as suggested earlier.

GT
 
PBW is an alkali cleaner, not the same as oxyclean. I don't know where this information came from, but it seems like a lot of people think that they're the same thing. I've had some nasty stuff that oxyclean wasn't doing much to, but PBW took care of it.
 
If it's mineral deposits, try white vinegar. You can get a gallon for like $3 at the store, I'd say dump two of those in there and top off with water.

If it's organic, up your oxyclean ratio (two or three full scoops), but make sure you mix it up outside first, oxyclean has a tendency to cake (shake a bottle of half a scoop and 1-2 quarts of water, dump it in, repeat, top off with water).

That's my two cents. Good luck!
 
Sodium hydroxide hasn't worked. I took a quart of liquid Drano, poured it in and added water to fill (7 gal). I'm wondering if that dilution is too weak though.

I'm about ready to go nuclear on this thing.
 
You can see the streaking in these pretty well.

carboy1.jpg

carboy1.jpg
 
Hot PBW for a day. Until you do that, you're just playing around. Which is fine, since its always good to experiment. But when you finally get tired of the stain, hot PBW should do it. I have yet to see anything that can survive a hot soak in it. Good luck.
 
Unless it has etched the glass you should be able to get it off. I'm all for getting more acid and start going for caustic cleaners as well. Maybe hydrochloric (Muriatic) acid would work? I think you can get that from hardware stores.
 
Hot PBW, Three Tablespoons to a gallon. By hot, I mean hot tap water. Be careful not to shock the carboy if it is cold. Let it warm to room temp first. Fill it to the neck, cover with saran wrap, let sit for a couple days.
 
Draino, although mainly consisting of caustic soda (lye), is formulated to sink and sit in the drain trap. It's not going to dissolve in a big jug of water and eat at stuff it's not directly touching.

You could probably get lye from a chemical supplier if you wanted to go that direction, but BE CAREFUL if you do.

You should probably post some pictures, maybe you've got something that someone else has seen before.
 
From the photos, the stains look like mineral deposits similar to what you see on shower heads in areas that have extremely hard water. Maybe try something like CLR? Information from their website below...

C Instantly removes Calcium deposits from glassware, decanters, tea & coffee pots.
L Instantly removes Lime scales from coffee makers, humidifiers, tubs, toilets & sinks.
R Instantly removes Rust stains from stucco, brick, porcelain, chrome & metals

CLR is the most powerful formula available for dissolving tough calcium and lime deposits and surface rust stains from tubs, toilet bowls, sinks, glass, chrome, fiberglass and stainless steel. CLR is septic safe and contains no phosphates.
 
This may sound stupid but....are you positive its on the inside? with the chemicals you've put in there it should be gone. it may just be on the outside.

John
 
This may sound stupid but....are you positive its on the inside? with the chemicals you've put in there it should be gone. it may just be on the outside.

John

If it is on the outside, then it can't hurt your beer. But even if it IS on the inside, at this point its fairly safe to say it can't hurt your beer. What are the chances that none of these chemicals can remove the stain, but somehow it gets dissolved into your next batch of brew? I say relax, don't worry, have a homebrew.
 
If you put too much more work into that carboy, you will have probably spent enough money to buy a new one. That said, it looks like calcium deposits from hard water perhaps, I say try the muriatic acid. Also, the Star San is getting cloudy likely because of minerals in your tap water making it ineffective, if you filled the carboy with distilled water you likely wouldn't have this problem, and it may work.
 
Muriatic acid is what is used in the fish tanking trade to get rid of hard water deposits. Wear gloves. And Rinse! rinse! rinse! when you are done.

+1 definitely looks like mineral deposits. Use muriatic acid; you can find it at most hardware stores. Or looks for something called Aqua Regia (it's HCl and HNO3 together)
 
Guess I missed the pics.

Does look like mineral deposits, and I've always had good luck using white vinegar on those. Of course, it helps to be able to wipe after soaking. Have you tried sticking a wash-cloth to a wooden dowel to get a bit of friction in there?
 
the Star San is getting cloudy likely because of minerals in your tap water

Nope, I used distilled water. That's why I got onto the mineral deposit kick.

The CLR doesn't seem to be doing much. Muriatic acid is up next!

I can get my carboy brush in there, and I've scrubbed furiously at just one patch for probably a total of 20 minutes. Nothing budges.

After the muriatic, I'm calling it clean enough. Whatever that guy brewed in here, I want the recipe! I've dropped maybe $20 into cleaning it. I had the star san and oxiclean anyway, so I've only bought $3 for drano, $7 for PBW and now $8 for CLR. In my parts, I can't even find 7g carboys, and the 6.5 ones are almost $50. I'll probably dry vinegar and ammonia (separately) at some point, those are cheap enough. What I've done to test is put about 1 gallon of fluid in, and laid the carboy down so it soaks one strip of the carboy from top to bottom. That way I have a solid line to check to see if anything has changed, so I'm not using much of any one chemical. Once I find the magic one, I'll fill up the carboy.
 
The "stains" look very similar to a time I etched my windshield's glass with a hydrofluoric acid solution I was testing.
If I were to guess, I'd say you have yourself a tiger striped carboy.:p
 
Vinegar and ammonia didn't work. Muriatic acid is sold by the gallon for $25, and that would put me at the cost of a new carboy.

I give up. As an Irish Taurus, that's really, really hard for me to say.

I'm actually considering taking my Dremel, which has the long flexible shaft attachment, and seeing if I can't attach it to my carboy brush. With a polishing bit it should be OK, enough for me to tell if it's etched on or not...
 
$25 for muriatic acid? Where are you shopping, SkyMall?

Go to a pool supply place and pick up a gallon for $3. I guarantee you it will eat that $hit right off in 5 minutes. Just dump some of it in and swirl it around. Be careful, because it will also eat anything that isn't made of metal, glass or plastic in about the same amount of time, including your flesh and clothing. Also, don't breathe the fumes.. it's probably mustard gas or something.
 
Is this a PVC (plastic) envelpoed Pyrex carboy by any chance? I have some that look just like that, but it's on the outside. They're used in the medical field in case the glass cracks, it's contained. Just a thought.
 
The "stains" look very similar to a time I etched my windshield's glass with a hydrofluoric acid solution I was testing.
If I were to guess, I'd say you have yourself a tiger striped carboy.:p

That reminded me of that Comcast Digital Voice commercial

"Sorry Roger, you tiger carboy now"
 
Back
Top