Howzit DS - good to 'sea' that you have it altogether ..looks great !..surf is calling !..I would recommend you look at sealing the ESC and battery ends with 'blue tac' and tape...don't know much about corosionX...but cant say I have seen it being the #1 solution to water intrusion. Water in the battery will corrode the terminals over time and water in the ESC will kill it in a short spate of time. Even though a number of manufacturers state that the ESC is water proof....it is NOT !
Prevention is better than cure !....sealing the electronics is like 'buckling up'