Endurolytes - How many do you use in an Ironman

I have Ironman Brazil coming up and am wondering how many people have taken in during an Ironman event ? I have used them in both cycling and running, but have yet to use them in a long event such as the Ironman.

My current plan is to take one every 1/2 an hour on the bike and probably at the same rate during the run. What do ya think ?

Thanks