I think you will find little success in reef keeping with air pumps/airstones, trickle filters.
IMHO HOB filters are only good to use as a "fuge" to grow a little macro if you are not runnign a fuge. Powerheads/wavemakers/closed loop are required for water movement.
Also be wary of a nano tank as your first adventure in Salt Water. I find it's hard enough and a big enough PITA with a 90 and water quality let alone with a small 5 gallon tank.
As "they" say go with as big as you can.. especially for your first reef
I think you will find most nano-reefers keep large tanks on the side or started with them before downsizing.