They short answer is that they don't over the long term. The issue isn't so much the food an oxygen but rather the lack of mineral replacement. Both plants and shrimp use minerals from the water which will eventually be used up thus killing them. It's the same reason why you can't keep plants and shrimp in pure distilled or ro water over the long haul.Spollack said:I could uncork and recork it (to allow fresh oxygen), but do the shrimp really need moving water? How do the ecoshpheres support shrimp then?