Fuel Tank Replacement Need Help

I have an 85 ski nautique with a 351 ford C in it. The other day my boat started hesitating and dieing out. We checked the carb and then the main fuel filter they where fine. Then i looked at the inline fuel filter above the fuel tank and found that it was filled with brown stuff. I then replaced the filter and the boat ran great for an hour. Then the same problem the filter was clogged. I went to west marine and the guy there said to use fuel tank cleaner because the tank has algie in it. I used it for the day but the boat started to dieing more than before and the filter was not clogged. I was wondering what size replacement fuel tank and who make the tank.

I live in Oahu Hawaii so my closest dealer is in cali and the shipping will kill me. someone told me about a compay called tempo and i think they have fuel tanks. Also is it possible to put a plastic fuel tank in.

you'll have to drain the old tank to remove it so why not just clean it out and reuse it? People do it all the time!

Pulled my fuel tank today and it was filled with brown algae. It is hard to clen out tried to pressure wash but did not work. The size of my gas tank is 56"L 11"T 12"W the closest tank tempo has is 46"L 11"T 10 1/4"W will this work even if it is 10" short.

The shorter one will work but you may have to shim both sides about 5 inchess if it fits between runners. Also check the width to make sure it doesn't interfere with the rudder or prop shaft. The "Brown Algae" in the tank is more than likely rust. If you clean the inside of the tank and do an inspection you will see several places where the epxoy coating has worn through. You can recoat but a plastic tank is a better alternative.