Two reasons: There are more nutrients in fUS than any of the known brands in the market place. Certain amino acids and minerals (even though we use a more soluble form of both) will not go into solution. When consuming fUS, the user should mix in 8 to 12 oz of water by shaking strongly for about 5 to 8 seconds and then consume in about 10 to 20 seconds. If the drink is left to stand for any amount of time it is a good idea to shake again.