Fuel tank algae
This past summer I bought a Cal 31, 1983, in Bellingham WA and brought her up to Seward Alaska. The 21 gal diesel fuel tank could not be inspected because there were no inspection ports. Before departing, I had two inspection ports installed, one on each side of the interior baffle, and than throughly cleaned the tank. I think this was the best investment I could have made because we did get knocked around some on the trip up.