How many liters can you get from this product?

The 2lb tub will make 38 12 fl oz servings by my figures that is about 14 liters the 38 servings is according to the label. The only product that helps my medical issues that are near fainting spells in nearly 30 years of experimentation searching for something that works for my inability of my system to absorb sodium.

triple the amount of *potassium?

Yes. I use it for longer training sessions when I know I will lose a lot of fluids. The extra sodium and potassium are probably not needed if workouts are under 90 minutes unless they are in extreme heat/humidity.

What is the difference between this product and the Gatorlyte packets?

Gatorlyte packets are a separate product, they are small packets meant to be mixed with another electrolyte drink (any brand) they have approx. 1000 mg of electrolyes, they are sold on Amazon. you can look at the nutrition information. I sometimes mix them with the drink but in the last couple of 70.3 Ironmans (San Juan and Silverman, both extremely hot) I would swallow the packet straight up (taste like filling your mouth with salt), then chase it down with a drink, I found this to be very effective in keeping the cramps away, if you can stomach it. Several years ago, I was racing Miami 70.3, I cramped up, I took one of these straight up, my cramps went away after a few minutes. It worked.