In candy-making terms, 234º is just a degree under the soft-ball stage, which ranges from 235-240º. That's the goal for candies like fudge, fondant, and pralines.
You can also check your candy for the soft-ball stage by dropping a small bit into cold water and seeing if it cools into a soft, flexible ball.
I prefer using a candy thermometer (see Amazon link in recipe card) to make this no fail fudge.