because cannabis is fat solable an not water solable these products on the market cannot clear your system because the cannaboids are left in your fat cells and at 225lbs it might take a bit longer to get out of your system.i dont think you can get all cannaboids out of your system in such a short time.you could try drinking a liter of water every hour for 4 to 6 hours before your drugs test and take 3 times the r.d.a of vitamin b12 to make your urine yellow.make sure you do as little exercise or anything that can make you sweat for at least 24 hours before the test as this will cause the cannaboids to leave your fat cells and pass into your urine,sweat ect...
best of luck hope something works for you:toilet_claw: