Every pool owner wants to get the most out of their swimming pool and one of the best ways to do just that is to extend the swimming season. In-ground swimming pool heaters raise and maintain water temperatures so that swimmers can enjoy fun and exercise in a comfortable aquatic environment more days of the year. While all in-ground swimming pool heaters can make pool water more comfortable and lengthen the swimming season, they do not all operate in the same manner. In fact, there are several different types of heaters for in-ground swimming pools, and each type provides water heating in a different way and offers different benefits. The following information describes the various features as well as the pros and cons of in-ground pool heaters and will help pool owners to make an informed choice between gas swimming pool heaters, heat pump pool heaters and solar pool heaters.