Does anyone know of a product that works to repel sand gnats? We have tried all sorts of DEET products and nothing seems to work. I'm not referring to the little gnat-fruit fly types that are on houseplants. These little pests show up at all times of the day outside and bite leaving big red itchy welts. I have read some people are allergic to whatever toxin they leave in your skin and that causes the welts. Also that they are attracted more to people who eat a lot of sweets. We are new to southeast Georgia (St. Mary's) and are not enjoying the gorgeous weather this time of year. Thank you!