Good lighting will do just fine, it will catch scraps from regular feedings. For crazy growth, spot feed a few times a week with bits of meaty foods like mysis, bits of silverside or scallops. Heck, some nems will even snag pellets if they land in the right spot!
whats your lighting? and the depth of the tank, and the depth the nems are in the tank... they're important as to the needs of spot feeding or not we just need some info to give you the right answers