Tony, If WalMart is 300 yards away and 1.5 gallons are $2, go with it. It doesn't matter if you use Walmart 6% or carboys at 12.5%, as long as you get your FC where it belongs and keep it there. I like the carboys because I can get them easily, easier than bleach and the price is generally good. Plus the jugs are reusable like deposit bottles. But the important thing is you are using sodium hypochlorite. In that, there's no difference between bleach and Liquid Chlorine.

As for CYA, it still takes 2-7 days for it to dissolve and affect the reading, so you cannot expect immediate results.

CarlD