Electrolysis and galvanic corrosion require a noble metal to contact the aluminium for the corrosion to take place.
Both types are accelerated with a current leakage to the hull.
Pitting with random round corrosion spots is usually under floors of boats where the humidity is high nearly all the time. It does not require any electrical charges to cause this, only high humidity especially in a salt rich moisture.
Determine which type of corrosion you are dealing with.