As far as disinfecting water, rather than bleach I'd recommend
calcium hypochlorite (available as swimming pool chlorine or shock.)
It's somewhat
cheaper, easier to use, doesn't taste quite as bad (it's what the military
uses in large disinfection systems), and if you get a pool water test
kit (the basic one) you can measure the residual chlorine. Just mix
some calcium hypochlorite with water in a plastic squeeze bottle and
add to the water you want to disinfect: Take a small sample out with
the test kit and get something between 5 and 10 ppm (7-8
ppm is ideal.) A one-pound bag of calcium hypochlorite was around
$5 at my local grocery
store, and represents enough water to treat a good-sized swimming pool
full of water (BTW, don't drink swimming pool water unless it's been
recently replaced, and then only if you can filter it.)
For smaller quantities of water (backpacking) I like Polar Pure, and then my
compressed carbon block (non-ceramic) filter. Ceramic filters can crack if they
freeze, and are somewhat delicate. - Dr. November