How do you store developer? The best way I have ever heard of and not my idea, was to take an empty wine box and with a flat bladed knife, remove the tap. Wash it out, fill with developer and replace tap. If you also reverse the box, it is easier to label and may stop you drinking developer, thinking it may be wine. If you squeeze bag when dispensing, it is an oxidation proof method and you even get a spring loaded tap to stop you wasting any.