You should run the gel until the phenol red tracking dye from the Novex Tricine SDS Sample Buffer (Cat. No. LC1676) reaches the bottom of the gel. Phenol red serves as an indicator of the running front as it is a very small molecule that migrates with the ion front in Tricine gels. The Coomassie from the sample buffer runs a little slower and can be 1-2 cm behind the phenol red.
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