Anywhere you have splash, a leak, too high of water bubbling all cause saltcreep. Those HOB water fall types like the penguin are the worst for saltcreep.
The cure is all the same, find out where the water is bubbling or splashing and make it stop. My Seahorse tank needs an air hose bubbler...and I have salt that even get on the lights. A real pain in the rear, but happy horses.