Newbie: Bromine and Clorox Questions

[muttrox]

Any help is appreciated!

I have a 17K gallon outdoor pool with a vinyl lining. I have always used a bromine feeder, because the guy who I bought the house from before me did, and I'm new to pools. And I used Burnout 35 for shocking (29% Lithium Hypochlorite).

For a couple years that was fine. Then after reading at this site, I stopped using the Burnout and switched to Clorox. I somehow came up with an equivalence of 3 bags of Burnout equals 2 gallons of Clorox. I've been doing this for two years now. I've never noticed any real issues with the pool --despite the next paragraph, it has always been very swimmable.

Whenever I bring my water in to be tested, the bromine residual is very low (0 or 0.1 to a reference of 2-4). And I've had problems with the bromine feeder, it eithers empties remarkably fast, or nothing happens. Yesterday, the man at the store said it was because I wasn't using granulated shock anymore. I asked him to explain, and frankly did not understand the answer at all, I am very bad at chemistry. Something about oxidation and converting back and forth. I have read Tip 10 over and over, but still don't follow it. I did think to go back and look at my printouts of the water tests. Sure enough, although the bromine residual is very low, my CYA is anywhere between 30-60, and it has a reference number is zero. I figure this is because they have entered in the computer system that I am a bromine user, so they don't think to look at the CYA number.

I'm not sure what all my questions are, but they're something like:
* What are the implications of using a bromine feeder and Clorox together? Is that bad?
* What is going on chemically by using both bromine and Clorox?
* Are the people at the store honestly trying to explain what's going on, or are they trying to sell me high-priced chemicals?
* This board seems to favor using exclusively chlorine as the way to go. Is that true? Why? If so, I gather I just need to wait a few weeks to get all the bromine out of the pool to do the conversion?
* I don't quite get the difference between Clorox and CYA. They are different, right?

Much thanks to all!