Aside from a shop compressor and filter, what else does the Shoebox require?

Although nitrogen is a very dry gas, its also very dirty. The paintball store I go to for filling my tank said they stopped using nitrogen for paintball tanks 10 years ago because of this issue. Even being a very dry gas, the contaminants and particles led to rusting and corrosion inside the tanks. Now they just use co2 with a quality particle and moisture filter.