I just acid washed my conical with DAC (basically super strength beer line cleaner) then acid soaked with ALC (Acid Line Cleaner) to finally rid myself of a hideous beerstone ring.
Question is, do I need to now scrub with BKF to “re-passivate”?
DAC appears to be sodium and potassium hydroxide which is different than BLC but in either case wouldn’t have harmed the passivation on the stainless. Any acid that will remove beerstone can probably passivate stainless anyway.
It won’t hurt to rub her down with oxalic acid (BKF) but it isn’t going to be necessary.
Another way of looking at it is that a lot of draught faucets and shanks are stainless. If passivation were required after using the line cleaners that micromatic is selling I can guarantee you micromatic would recommend and sell a third product for passivation.
I followed John Palmer’s recommendation in the book and gave it a good scrub down with BKF then rinsed well, toweled off and let dry in the sun for a few hours. doesn’t look like the BKF did anything different, but what the heck.
that said, I am so happy now to have a conical that looks as good as new again - I tried everything to rid myself of beerstone, and this did the trick.