Magnesium sulfate / potassium sulfate / sodium sulfate
"I drank the first round at 3 p.m.  I managed to get it down and drank water, gingerale, sports drinks. I mixed it with berry Propel water. I also ate orange jello. At 2 a.m. I tried to finish the second dose but couldn't due to severe nausea. Now it's almost 4 a.m. and I'm still trying to drink water without vomiting. The taste is very sweet and salty. The split dose is for the birds. You still have to  drink 48 oz. of fluids. I don't consider that low volume.  If I ever do this again it won't be with Suprep."