[trapae]

 For a little while now, I've noticed a whitish film on the underside/inner portion of the lid of my dome of my stainless steel fermenter.  The rest of my fermenters still shiny and new looking.   The part under the dome I don't think even comes in contact with wort or probably even the Krausen.   Anyway it is getting worse and I'm wondering if it is due to my hard Water or beer stone.   Scrubbing with hot PBW has not worked. ( although I have only used a micro brush scrubber because I'm worried to scratch. ). My normal sanitation with star San has not removed it.    Up until now I have been worried to use anything else or do any serious scrubbing because I don't want to damage the stainless steel underneath. I'm not sure what type of scrub brushes are safe for the stainless steel without scratching it.   I was planning on using undiluted star San next.  Not sure if  barkeepers friend is safe to use on the stainless steel of the fermenter? Anyone have a good system for removing this that won't  damage my fermenter? Thanks.

[Stevie]

My guess is calcium from your hard water. Try soaking and scrubbing with starsan, maybe a slightly more concentrated solution. Lactic acid or CLR might work as well. I have hard water as well and rince my fermenters, kegs and bottles with a bit of starsan after cleaning to help reduce this.

Using PBW of cheaper cleaners, as you're already doing, is a good thing to do with hard water. It has additional additives that are meant to prevent the buildup, but I guess some water can be just too hard.

[ethinson]

The same company that makes PBW makes a product called B.S. Remover (Beer Stone).  If I remember correctly from the sanitation seminar at San Diego NHC you need an acid to remove it.  StarSan is a weak acid, but I think for BS you need something stronger.  CLR might work as well, since that's designed to remove hard water/rust type stains.

I'd be curious as to why it's only on the lid.  That part doesn't make sense to me.

[swampale]

I had beer stone on my Blichmann conical a few years ago. PBW removed some, but not all. I used BKF with a white scrubbie and it did take it off, but it took awhile. I had to scrub a lot and was nervous about ruining my conical. It seems to be okay now and I keep an eye on it rather than just give it a quick wipe, rinse and walk away like I did a few years ago.

[ynotbrusum]

Regardless of the method, if you are going to soak stainless, just keep an eye on it - once the stuff/gunk easily comes off, get the stainless item cleaned up and rinsed, so you don't cause a corrosion.  The stainless should re-passivate with exposure to air.

[Philbrew]

I had beer stone build up inside bottles, especially on the bottoms.  I tried an overnight soak in BS Remover.  It did NOT work.  A 5 minute soak in a 20% muriatic acid (hydrochloric acid) solution cleaned them up nicely.  I think a 10% solution would also have done the job. 
I don't know if that would be a good idea for SS.  Forum comments?

[trapae]

 So I looked a little more and it is actually on the underside of the flat part of the lip just touches the rubber gasket. So not sure that it is a beer stone. I tried Undiluted star san and didn't work. I tried barkeepers friend with a soft scrub and didn't work. Not sure what is going on.

[trapae]

 What if I took my Dremel and a soft polishing pad and polished the entire inside of the lid to get the buildup off and then re-passivate? Any comments?

[Stevie]

Try barkeepers friend first

[majorvices]

Try vinegar cut down 50% with water before you try a dremel or anything like that. Most of the commercially available acids used fro cleaning in the brewing industry will knock that stuff off very quickly, but I bet you the vinegar will work.

[hopfenundmalz]

Try vinegar cut down 50% with water before you try a dremel or anything like that. Most of the commercially available acids used fro cleaning in the brewing industry will knock that stuff off very quickly, but I bet you the vinegar will work.

I asked John Blichmann what I should use on my conical. He said vinegar is effective, and cheap.

[trapae]

 OK thanks, I will try that next.