Help identify what died in my feel chamber

[Ylbc]

Recently started getting a strong almost sour odor coming from my ferm chamber. And in the picture you can see these white deposits that have showed up. Ive tried washing the walls and floor with a bleach water solution but it comes back, any ideas?

 

[augiedoggy]

I could be wrong but im going to guess you put kegs in there that were dripping wet with an acidic cleaner like starsan or beer itself? these acids will attack and dissolve the aluminum. that or you used a cleaner on it that eats aluminum and didnt wash it all away? even pbw or oxyclean eats aluminum.. this is why the spider arms in a newer washing machine are made of it so they dissolve with use creating planned obsolescence and failure to sell more washers as I recently discovered.

even bleach can stain aluminum if its not removed well.
https://www.ehow.com/info_8778746_bleach-do-aluminum.html

 

[Ylbc]

That's very possible. Would it great a harsh sour smell?