Ive done this and its worked many times. I love cannabis and smoke 5-6 blunts a day. I was on reporting probation, and had random drug testing. I had to call a number every day, and if they called my color (red) then i would have to piss. I had to do this at least 1-2 every week. I didnt use certo or pectin, i used SureGel, same thing. But how i did it, id call my number, if i had to go in then i would go to Kroger and get suregel and a purple gatorade (the big ones from gas stations). i would take a big ass drink to clear about 2" of room, and pour the suregel in. mix it all up (better if its warm). there will still be lots of clumps and shit at the bottom. i would drink this 1-2 hours before the test, and made sure to piss 3 times before i went, and take a water with me on the way and kill that on the way. then had to wait in the line and by then i feel like im gonna burst, then when i piss its clean every time. i went to jail in the end though, but only because i started saying fuck it and quit goin lol. they said if i went to jail for the 3months then they would take me off probation, and they did.

It works for me!