Nems put off a lot of waste, I would say you CAN do it but like mnat said, constant water changes and monitoring would be completely necessary. What is the time frame on housing it like this? It will need light also, And especially a heater.
IMO if you keep the water quality right, it should be ok, presuming you have proper lighting and proper flow. LFS's have that setup for anemones every day, so it can work. It's just a matter of water quality, light and flow. Planning to do water changes as a routine is good, but also plan on doing them as needed based on nutrient levels, and also alk/pH if you're not doing the tank.