I am posting this to both Trawler World List and the Great Loop List, since the recent question arose on the Loop List and my original call for help and the many responses that I got were from TWL. Hope you don't mind getting this twice. SNIP>>>A boat that I'm interested in purchasing has iron fuel tanks. Would >appreciate any comments, pro or con, as to iron tanks versus aluminum or >fiberglass.<< (from the Loop List) Miss Jackie is currently in the Keys Boat Works undergoing the major surgery of having her iron, steel, whatever, rusting tanks replaced with Aluminum tanks. We've been stuck in this hotel room for over three weeks now. Virtually all Taiwanese and many other boats were built with ferrous metal tanks, which, of course, don't rust from the oil-coated inside. If they are not well-painted, as mine weren't, they can rust from the outside. And, just like any other water damage that may occur on a boat, it's not the salt water that causes the most problems, it's the fresh water that comes in through leaks, open windows, or condensation. The bottom of the tank has to sit on something. If the something is not well thought out vis-à-vis moisture collection, the tank may sit in water. Eventually, it will rust there, and unfortunately, the place it rusts, since it is sitting on it, is very difficult to inspect (or repaint). In my case, the leak is very difficult to see even with the tank out of the boat in bright sunlight. The extensive rust tells me that they would have leaked eventually, but most of the rusty spots did not leak. But then, it only takes one, and the first one is the one that counts. ANY metal tank will corrode if allowed to sit in water (except gold or silver, I guess). My Aluminum tanks will outlast me and the boat. I consulted the TWList (many thanks to all who responded), the Web, and local yard managers and welders before specifying the tanks and means of protection. Here's what we did (the tanks are 225 gallon saddle tanks with shapes that conform, sort of, to the hull): The tanks are fabricated of 3/16 5052 Aluminum with three fully welded internal baffles (the old tanks were 1/8" steel, with two spot-welded baffles). Connections to the tanks will be stainless steel. The tanks are coated with Gluvit (an epoxy) before installation. This is "belt and suspenders" protection, since Aluminum is self-protecting, but the yard manager strongly recommended it. Aluminum Oxide is used for abrasive grit, it is so hard. The beds for the tanks are 3/4" plywood, coated with epoxy, attached to the ribs of the boat (the old tanks sat directly on the ribs). 2"x4"'s are fastened to the ribs vertically, and a 1/2" plywood bulkhead attached to them. There is a 1" air space between the bottom of the bulkhead and the tank bed. 2" rubber strips, 2" apart, are attached with 5200 to the bottoms and sides of the tanks, ending about 1/4" from the corners, so there's no place for water to collect and the tanks are nowhere sitting on wood or fiberglas. A grounding tab was welded onto each of the tanks to provide a secure connection to the ship's bonding system. The bill for this is going to be around 20 BUs, however, we're having a lot of other stuff done while the guys are in the bilge and the engines are out. The original estimate was 16 BUs. Dave and Marie Ross Miss Jackie II Tiger 41 Sundeck Reston, Virginia Docked in Marathon, Florida