FWIW my younger days of keeping nems I never spot fed at all, ever.
When I first joined here I had already had my crispa and LTA for a year and a half before even hearing about spot feeding, and they got HUGE, too big.
I firmly believe light is their main source of energy.
I know Melev never spot feeds in an effort to keep his nems from growing too big too fast, and they look very healthy.
A new nem, I would not even worry about feeding 2-3 weeks to let it settle, unless it was bleached, and then I would only feed mysis to nurse it back to health.