You might can get male or female for a pair, depending on which dragonet you have now, but long term with these fish are difficult to keep due to its feeding habits. Two will require twice the food source, some have success over a year, but many lose them...
The male has the much longer dorsal fin... two males will fight, but you can have two females
They are lovely fish... fun to watch with great personalities. Sadly even with supplementing pods, I lost mine at around the one year mark and I tried again, the second one also lasted about a year, as much as I love them, I decided my tank just could not support them.
If you give two a go, check out Paul B pod feeder.
http://www.saltwatersmarts.com/diy-target-feeder-mandarinfish-pipefish-2804/