From personal exp, its really hard.
nems need high par lighting and great filtration/water quality to keep alive.
Really hard to do in such a small volume of water with parameters easy to fluxuate from high to low if not kept in check very constantly.
I sold my nem due to this.But the first time I kept a nem , It died shortly after due to the reasons mentioned above
I kept it in a 10g with hoosting clowns, shriveled up and died after 2 months.