Shireen-

After doing the calculations again. Here is what I think will work for you.

Take 2 cups of warm water and dissolve 1/2 of a pinch (about 10 salt crystals in the water.)  I know it doesn’t seem like much.

I have worked the math like 5 time to make sure that I am right, it is still comes up the same. If you haven’t tossed your bottle that you bought I would just rise it out and use it again. (Fill it with what you have made and dump the rest.)  I hope this works for you.

 Robin