Make sure to wear gloves when putting your conches in the solution, as well as when you remove them.
If barnacles are being stubborn, chisel them off using a hammer and screwdriver. Angle the screwdriver under the barnacle and gently tap on the end with the hammer. This should dislodge the barnacle.
If some dirt or stains are not coming off, use your thumbnail to gently scratch them out of the shell.
It can sometimes take conch shells awhile to completely dry, especially if you live in a cooler region. It is not unusual for shells to take a couple of days to dry completely.
If you do multiple coats, let the shell dry for 12 hours between each coat.
