My O'Day 322 has a 2-burner propane stove with an oven. The PO used 1 lb bottles (left them all over the place. I bought 2 small (5 lb) steel tanks on amazon or eBay for $50. They fit into the ultra small propane locker ( won't fit a 20 lb tank). They are small, but 1 bottle has lasted a year (I don't use it all,that much, but have baked pizza in the oven, warm sandwiches in the oven, cook coffee and breakfast on the stove periodically.
The PO also plumbed a quick-disconnect near the rail,grill, so you can just "plug in" a hose to fuel the propane grill, and remove the whole thing when you don't want it in the way.
I am in fresh water, so don't worry about corrosion (although these little 5-pound tanks seems to be holding up,ok).
http://www.ebay.com/itm/Manchester-...713288?hash=item46120f73c8:g:peoAAOSwZ8ZW9Fp6