The difference is marketing hype.
Here is the differnce and how most people think about their pools.
Here is an example for you.
Tabs in the orange bucket. Put 3 tabs in a floating dispenser.... etc etc so it says on the instructions...
Shopper 1 looks at teh orange lid tabs... "OH Lookie there, on the shelf by the tabs is a cute dispenser that looks like a frog. I will take it! "
Shopper 2 looks at orange lid... frog needed.. Shopper 2 says .. "****, and I have to buy even more stuff...on and on and on with spending money."
But on the next shelf is the yellow lid... just drop one in the skimmer and I dont need to spend even more money on a frog? "THats awesome! I will take it."
Both shoppers just bought the same tabs.... and that is marketing hype and you have been hooked.
the pool stores and the manufacturers are in business to sell you stuff. That is what they do and how they make their living and they will try their hardest to do whatever it takes to sell it to you. Even to the point of untruthful.
Whether or not its the best product, or method to maintain your pool is not their concern. That is all there is to it.
It is your pool. So therefore, it is YOUR responsibility to learn how and then to maintain your pool.
RIght Here, in this link, is everything you need to know how to cost effectively maintain your pool without spending all your money by being suckered by the hype experts.
http://www.troublefreepool.com/content/
i wasnt going to add them to the skimmer just wanted to know the differance between the two, but i have read that the tablets raise CYA to levels that make clhorine not work as well.....so bleach is best?