Lots of owners have. It's the nature of Aluminum tanks and having them mounted on the hull side, underneath the air intakes. 23 years is a very long run for Aluminum. There's another thread on Ocean fuel tanks.
Aluminum tanks only last so long... nature of the beast. Never understood why builders of "quality" boats use aluminum tanks when fiberglass tanks last forever.
Well, that's what everyone thought with fiberglass tanks and gas boats, but that ended up not being the case when ethanol started getting put into gasoline and eating them up. LoL On yachts, I don't know either. Hatteras has been using fiberglass tanks since the 1960's and no issues with them with diesel at all. The aluminum allows a little extra flexibility on where they can be put, but fiberglass is the way to go IMO
Correct about Ethanol but not an issue with diesel. The tanks on my boat are 47 years old Of course who knows what additive bureaucrats will put in diesel one day ...