I think it would take 2 1/4 gals of 5% regular bleach to equal one pound of 65%cal.hypo....That walmart 54.6% bag sounds fishy to me.....Oh by the way I pay $2.15 per pound (thats including shipping) of cal. hypo from "in the swim".
Although it does cloud the water some what, if you put it in late in the evening its cleared up by morning.......You must make sure that all the cal hypo disolves and you should brush the pool floor after you add it, if you dont it will bleach your liner.........I like to use cal hypo as shock but I wouldnt use it just to keep my residual up unless I could find a cheap supply of those plastic covered cal hypo sticks, does anyone even sell those sticks any more???