Rust in the very bottom of my cornelius kegs

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Rust in the very bottom of my cornelius kegs

Post by Wozboy » Thu Feb 11, 2021 9:06 pm


I have rust in the very bottom of two of my kegs and what I'd like to know is would it affect the beer? I'm guessing it's not a good thing so clarification would be good, I'm presuming it's bad and I shouldn't use them.

Can this be cleaned or treated? I can't reach the bottom of the keg at all so that's not an option, it needs to be remote cleaning somehow. Is this possible? I hear about lemon juice and some acids?? I know this has been answered on some posts but I need step by step instructions I can't follow the science, it doesn't make any sense to me!

I'd be grateful if somebody could help, I really don't want to lose two kegs because of a little bit of rust.

Many thanks in anticipation of your valuable advice, I'm based in Wakefield, UK, so I need stuff available in the UK.



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Re: Rust in the very bottom of my cornelius kegs

Post by Jocky » Fri Feb 12, 2021 8:12 am

If it’s definitely rust (you’ve tried soaking in sodium percarbonate/pbw with a kettle full of boiling water?) then I’d throw in some citric acid or bar keepers friend and a little water and leave it to soak, giving it an occasional shake.

You might need to repeat that, but putting a scouring pad on the end of a stick will help after the first soak.

What would worry me is how deep the rush goes. Corny kegs aren’t that thick, so before you next use it put some water in and pressurise it for a few minutes to check you don’t have a pin hole now.
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Re: Rust in the very bottom of my cornelius kegs

Post by Carnot » Tue Feb 16, 2021 9:44 pm

Pitting corrosion on stainless is possible but requires extreme conditions which I would very much doubt would have occured with a corny keg on beer. The thing to avoid on stainless is wire wool which can leave fragments of steel which will corrode the stainless. Alkaline cleaners will not be very effective against rust as it is insoluble under such conditions. I would mechanically clean with a nylon type scouring pad and look for corrosion pits, which I would doubt as this would require a deposit and time. Once cleaned then I suggest you passivate with citirc acid, which will also take care of any light rust film. 4-10% citric acid for 20 mins at 21-49 deg C. See link below. Oxalic acid on stainless should be avoided. Likewise never use chlorine bleach or hydrochloric acid on stainless steel. ... ss-steels/

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