Stainless Steel reaction to Aluminum in Salt Water
I worked in anodizing and we had more than one set up with about 10 dip tanks each,
a computerize crane choosing which dip tanks to use according to the task and how long to immerse at each station
and what the sequence would be.
All done automatically. The size of each of the individual dip tanks of the set is about 8 feet deep, 4 feet wide and 14 feet long.
Good for large aircraft parts.
You can not imagine the expenses in building this and processing the chemicals.
All of which points to what anodizing is.
And nobody is properly trained to use the equipment, and bosses get in the way
of making a good product (out of negligence, ignorance, or other emotions,
you have no idea what our social (anti-goy) caste system lets lose on engineering platforms).
The question is: is your aluminum properly anodized.
Online metals have materials for further research, including marine applications.
Even if you don't buy online, I find the information they provide most useful.