I dont think you can use them from the first week,i have been having it since 2nd week but i think some cdcs say 3rd week,they are £4 something a tub and have 15 servings,if you do make 1 either mix the powder into the sachet first or have it going in the blender and add gradually,this is mainly for mixing a tetra,if you dont do this as soon as it hits the water it will congeal and wont work
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