I like to use Pyrex or Kimax brand Ehrlenmeyer flasks for mixing and storage. You can get them at a science supply. If you don't get the heat resistant grade of glass they are not that expensive. The nice thing about them is that you can mix chemisty without sloshing it all over and they contain chemical powders better than open containers. I have them in 250ml, 500 and 1 liter.