Hello, try potable aqua tablets. Check out the camping section at Wal Mart.
You want the single bottle, not the package that has 2 you have to mix.
I just put a couple in a quart of gatorade, let them dissolve & drink it.
I would STOP smokin now, and drink about a quart a day for about 4 days
before the piss test.
A few years back I was all a mess & was smokin, snortin, and I don't know what all & I drank about 3 quarts that night and another quart on the way to the clinic and I passed. They did send it on for further analysis but it came back ok & I got hired.
Hope that helps.