I had a nano setup with some equipment, but it's 8g not less than 5:
8g rimless curved glass finnex tank, back painted black
70watt HQI k2 viper (no ballast) + 14k lamp (new)
70watt HQI ballast brand new from illuming dot com
MaxiJet 900 + tunze nano filter (holds carbon etc. and produces a good amount of flow and surface skims).
70watt eheim jager heater
and probably some other stuff. Let me know if you're interested.