Fueling during marathon swim training

I have been an open water swimmer for over 18 years. During that time, I have tried numerous products to fuel my training and to consume while swimming a marathon. The goal of liquid nutrition is to get a great source of energy and hydration from that product.  I have found that many products may taste great on land but after swimming for several hours in salt water, it does not.  We are all individuals with our own likes and dislikes.  Testing a product is done during several training swims. I have enjoyed these products with great effect:  Maxim, Hammer Nutrition Ultra Endurance Fuel (unflavored), Nature Smart CarboPro (non-sweet neutral flavor), UCan Super Starch (low carbohydrate).  Also, I have added a very small amount of powdered Gatorade to lightly flavor such products as Maxim, Ultra Endurance Fuel and CarboPro. Every few hours I drink plain water.  About every 5 hours during a marathon swim, I like real food such as half cup of canned diced peaches in heavy syrup or a Fig Newton cookie.  These products work for me.  You may want to test other products not listed here.....Go for it!  You know your likes and dislikes better than anyone. I can't emphasize enough to test these products during a long open water training swim.  You may discover for yourself that your mother's oatmeal cookie may taste great at home but after swimming for several hours, the sweetness may be nauseating. But on the other hand, it may be a taste of heaven...you be the judge.   Again, test these products before you swim your marathon.  You'll be glad you did.   Happy training!