wow! just read the decription on the Prime by Seachem seems it is really a very economical way of detoxifiying the tap water. 1ml is to 10 gal of water... if you don't have a medicine cup i would suggest using a teaspoon which is 5ml.
i have been using stress coat for months already and it does consume a lot... it's like 1ml for 1 gal of water. I do a strait from tap and then titrate the water flow with the dosing. it works fine for me and for all my fish.