WTF Happened to my MAP tank?!?!?!

[APD99]

I left my MAP in the drawer at work over the weekend. When I left friday the tank was empty and when I came in this morning ready to fill it up this is what I found. I've opened it up and tried to clean it with isopropyl and with hot water but it won't come off? WTF did I do?

 

[Turbo]

At first glance it looks like vapor condensation, but w/ your description it seems like your juice may have corroded/etched the plastic? What kind of juice are you using? Juices w/ acidic acid (fruit, cinnamon) can do that..