... plan is to run 150ft of 120 to pump in conduit to a weatherproof GIF outlet... will hook up to own breaker in fuse box... how heavy a wire must I run?. did I simplify this too much?

Please provide the horsepower of the pump motor, and the load of any other equipment that may use this circuit, and what size amp circuit your planning to run. The simple answer is just use #10 wire, but there may be a case for #8 wire.

Tk russel... thankyou for reply:
1. 2hp motor... pool light plugs into 120
2.amp of circuit... don't know--that would be the breaker I buy for box?
3. yes, I learn as I go...