fuel tanks:

fuel tanks have a finite life.aluminum fuel tanks,in a sea water environment,in a smaller boat,have a life span of approx 10yrs,that's it...yes,some last longer,and some shorter-10yrs is the expected life span.over the course of being in buisness,i've had a few customer's boats,that developed a leak in the fuel system over the "off season",better for it to happen on land,then out in the water...
listen,if you've got an older boat,you need to check it out before it becomes a big problem.there's no other way to check it out,other than,phisically removing the tank.sorry...the top of the tanks usually look good,problem is down below.i know this isn't something you guys wanna hear."if it's not broke,don't fix it",right- waiting till you have a huge problem,fuel in the bilge,is the choice you're making...your call...smart play is to check it out...if the tank has erosions on it,it needs to be replaced...other's will tell you,this is repairable,again,your call...i've read all kinds of insane things regarding fuel tanks...do yourselves a favor,use common sense,when it comes to the tank...
but,i highly reccomend everyone inspect the fuel system on their boat-inspect it the proper way...