No, you do not need a dedicated candy thermometer. Any thermometer will work just fine, as long as it can measure up to at least 180°C (preferably a little higher). In our opinion candy thermometers are clunky and in the way. We strongly prefer using this thermometer from IKEA (called FANTAST). Super simple and sturdy and can also be used as a meat, dairy, "whichever other food you need to measure" thermometer.