I'm with Brian, Huram!

I mix what I need for one session, use it & dispose of it. I do store used fixer in two different bottles...one for used (ie depleted) fixer and the other for fixer used once. If I've done a lot of printing, I do not re-use that fixer.

I'd say that because your darkroom is also a food storage area, it will be very important for you to keep things in there clean. Also, make sure that your work surfaces (especially where the chemicals are used) are non-porous! You do not want chemicals soaking into wood shelves! That was why I suggested a plastic table cloth for that area.

One of the things I do in my darkroom is keep a container of Lysol cleaning cloths. They come in one of those plastic cylinders like window cleaning cloths. I clean everything after each session and wipe down the 'wet area' surface with those cloths.

I keep a sponge 'scrubby' just for cleaning out my trays...and to show you what kind of a freaky sort of person I am.... I have separate measuring cups marked "D" and "F"...AND (as if that wasn't odd enough)... I ALWAYS wash my trays from developer through fixer! haha Geez....I sound like a bit of a nut case, here! haha
So, buy yourself an apron, and get cleaning! haha