There is no way to answer the question as asked. The terms "Green Light" and "Spectracide" are brand names, and each brand includes products that may contain different active ingredients. There are other brands as well. In fact, there are more than 100 products labeled for use to control fire ants, but these products contain only a dozen or so common active ingredients. You need to know the full name of the product and its active ingredient(s). In general, most products are effective and pose minimal risk when applied as directed. The trick is to compare characteristics of the active ingredients, concentrations and price (or the cost per ant mound treated). Buy the most appropriate product for your situation, and use it strictly according to label directions.