I use the aqua-tainers as well. I've never had one leak when completely sealed, and I've only had one where the nozzle contraption leaked, and I simple traded it with one that I wasn't actively using to get water out of. THe 7 gallon ones are great, but I keep quite a few of the 4 galon ones too, simply because they're light and easy to lug and refill.
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"2+2=4 is not life, but the beginning of death." Dostoyevsky

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