I did a nickle of some complimentary time and if you're on REAL probation here's some real friendly advice. First all the stories about urine and condoms (which doesn't seem to apply to you), etc. could work. Your problem is, as Stove's pointed out, temperature. Should be a strip on the side of the bottle. And let's keep this thing REAL. What are you gonna do? Shove someone eles's shit up in you PRIOR to going in and hope it don't break? Also, the PO generally watches you piss, right? If not, you're in a place I NEED to come and commit crime as that's STANDARD protocol. Now that the rants over for background, let's look at some options that are TRIED and TRUE:
Porn joints generally carry detox products. Just get the name, pull their website up, research their chemicals and cross-reference as to whether or not they are diuretics. I used detoxl's stuff back in the day. Used to have a website, but the porn joint out here still carries 'em. I don't buy them anymore, my old lady and I simply like the First Amendment.
Now, the old water game. Yup, good way to go upstate REAL fucking quick! Why? A diluted sample is the same as a DIRTY sample in the eyes of the law! I know!
You can get a 5 panel tester and a COC strip for about $10 bux and check ur shit in advance anywayz. Pot is your 30+ day hit. Bad shit as I don't care how skinny you are it's gonna hold. Coke 3-5 days. Your pills and shit depend on quantity and bank on 30.
Abstinenece is the best policy, but you aren't gonna do that. So, I'd HIGHLY recommend you wave off on any of the folk remedies and get some cash and do some research. I called my buddy to see what she's on and will post it when I find out. Good luck!