Yes you could....It depends on your tank size too, but note that Excel is a carbon source not a fertilizer.
The reason why it depends on tank size, is that if you have a large tank, it is not economical to use that much excel when pressuraized CO2 costs 60 bucks a year.....makes no sense, particularly when it is a more preferred method of Carbon delivery. If y ou have a smaller tank, then go for it, but also learn more about macro and micro dosing. It does help in keeping BBA at bay as well. <but so does proper CO2 delivery>
P.S. I like the skittles/popcron combination...it kind of reminds me of fruit loops.
It's my understanding that the excel has a mild algaecide in it. That is why it also seems to kill anacharis and sometimes vals. Excel is still a good choice for smaller aquariums. As previously mentioned in larger aquariums it will get more expensive when compared to injected Co2 in the long run.