First, what type of fish are you talking about?
There are two (if not more) species commonly called needle nose gars at many fish stores.
1. Lepisosteus osseus- TRUE needle nose gar (More commonly called Longnose Gar)
Grow to around 3 feet in aquariums and need over 300 gallons.
Native to North America
Ganoid scales (armor)
Dorsal and anal fins DO NOT line up.
Nostrils at end of mouth.
2. Xentodon cancila- Freshwater Needlefish (MISTAKENLY called Needlenose Gar)
Grow 10-12 inches long and are a freshwater species related to the marine needlefish.
Dorsal and anal fin line up symmetrically.
Tiny scales/ May appear scaleless