My boat's over 30 years old now. When she's out of the water the hull gets pressure washed and re-waxed. It's all discoloured and shows signs of pitting, just like the older exterior uPVC panels on my house. All the day-fishers I talk to say algae is the cause - I live in ignorance I guess could be an old wives tale but clean her every 3 years or so regardless.
Found this:
Blister Repair Methods
Sure this thread should now be in Tech Log
