Large bags of spinach needs more ventilation to keep moisture low. poke holes on the front and back to prevent moisture build up and rotting.
You can also get fresh produce storage containers ( https://amzn.to/2upeJKN ) which have vents for the fresh produce to breathe and stay dry.
Or you can get it in a can of spinach:
http://amzn.to/2eX3NME
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