Fishing in salt water exposes your equipment to some of the harshest conditions possible. Salt is the enemy. If left unchecked, it will destroy your equipment.
As a routine, we soap our rod and reels after each day of fishing.
I say if the salt goes there, the soap goes there. After the reels have dried, we give them a light spray of lubricant and then wipe down all of the excess.
One key factor to both of these steps is to fully lock up the drag during the process. This will squeeze the drag washers together and keep the fluids from getting in.
After the cleaning and oiling, we back the drags off and this lets the drag fibers expand and not get stuck together.
We always store the reels with the drags backed off. Just don’t forget to make resetting them part of your fishing routine on the next trip.