Likely Reef Tank Suitable
Likely Fish-Only Tank Suitable
These fishes belong in the Order Gasterosteiformes and Suborder Syngnathoidei as members of the Family Syngnathidae (Seahorses & Pipefishes) consisting of 2 Subfamilies, 52 genera, and 200+ species, and Family Solenostomidae (Ghost Pipefishes) consisting of 1 genus, and about 6 species.
Although most are found in seawater, some are found in freshwater. They are fairly inexpensive, somewhat colorful and very hardy in the right environment. Like their Seahorse relative, requirements are basically the same. In fact, they complement each other in the reef/invertebrate aquarium and require much the same food/conditions as do seahorses and dragonets.
For in-depth information concerning these fishes, checkout Reef Fishes Volume 1 by Scott Michael (ISBN #1-890087-21-1). You can see a review of this exquisite book by visiting my Product & Book Reviews page.