How to fix- Bad gas or E10 effected gas

[ChickenNecker]

My boat has been sitting for about a month or longer with about 15 gals in a 50 gal. tank. The gas would be e10. Would it be bad to run the engine on that gas if it has gone bad? Should I treat the remaining gas(octane boost, water treatment) and run it out and then refill? Or, fill up with new gas? Will the new gas mix with the old(bad) gas so it will burn OK. I dont want to pump the tank becuase I have no where to put it so Im looking for other advise. Thanks

[fishingfun]

The gas should not be bad after a month or so. I have been using E10 gas and my boat sat for several months in the winter with no issues. Just make sure you have a good seperator and maybe add some Sea Foam gas treatment.