Howdy 66200:
Sugar? or Salt?
How much? In to how many gallons of gas?
The safe thing to do, when in doubt, is to remove, drain and flush the tank. That's easy to say, but so much work to do. Simply siphoning of the contents of the tank won't get anything that is not in suspension.
Other details and investigative info- Is the engine still able to run? How well, or badly? Do you have a filter between the tank and your fuel pump?
Sorry to give more questions than answers, but that's the nature of problem solving over the internet.
Adios, David