The BEST bottles for chemical storage (liquid or powder) are in your waste basket: soda, water, juice: the clear, brittle plastic ones you see everywhere. They do not 'breathe' and I keep color dev for YEARS. But.....you MUST fill to the very top and they don't 'squeeze' well. Get different sizes. I also use 50 ml liquor bottles I occasionally find on the sidewalk. Of course, glass is just as good.