I don't have a heater recommendation. All the ones I have used have work just fine. I do recommend though getting a tank thermometer. Even just something simple like this https://www.amazon.com/Jansamn-Thermometer-Adhesive-Aquarium-Kombucha/dp/B07JVRJ9Y1/ref=asc_df_B07JVRJ9Y1/

Heaters heat well but but I only moderately trust that what you set them to is accurate.