We made a large pan of salt potatoes (as well as other foods) the other night for some out of town guests. Later in the evening, as well as all of the next day (no we didnt get around to doing the dishes), there was noise coming from the water. The sound made me believe that maybe the salt solution was going in and out of supersaturation and that the salt crystals were forming and falling to the bottom of the pan and making the noise. However, there were no solids anywhere to be seen in the pan. I could think of no other explanation and figured I would either ask Cecil or the Teeming Millions because someone must know why there was so much noise and why for so long. Thanks all.
What was the pot made out of ? If the salt was a bit acid, you might get some bubbles/corrosion. That could make a noise.
-Welcome to the SDMB 
Did this noise occur before you added the potatoes?
(I ask because it would seem unlikely that supersaturation could occur when the potatoes (or parts thereof) were providing nucleation points for the formation of crystals).
I believe the pot was an older aluminum kind. I should have taken the water out of the pot but had more pressing things.
The noise, something like grains of sand dropping onto metal, occurred after I had taken the potatoes out of the boiling water. It may have occurred during but I don’t know. And again it was making the same noise the entire next day even though the water had cooled. And still no solid crystals!
By the way. I didnt make the water real salty like they suggested. I used about half the bag of salt, so there was no crystals to be seen or lying on the bottom of the pan, before the potatoes went in.
We have hard water. Which may or may not be an additional factor.