Last summer I ordered Plantex CSM from a place out near Lancaster, PA. I received a 5 lb. bucket of the stuff and I use 3 teaspoons per 300 ml mix of my PMDD concoction. At my dosage rate of 3-4 ml per day in my 55 gallon, I'll never use the stuff up! If anyone is interested in buying any please contact me off list for details. John Haydt Philadelphia