[1][5][6] Adults may be found in or just above sandy or muddy substrates, around the base of macroalgae, especially red algae, or seagrass and close to or within coral reefs or rocky outcrops.

Because they are so small, the brood pouch is also large in proportion to the body, giving the males a somewhat more seahorse-like appearance than the females which have the typical slim linear form of pipefishes.

The brood pouch extends from just behind the anus to about halfway along the fairly short tail and is relatively large compared to the small size of the fish.

The eggs are incubated within individual skin cells in the brood pouch, hatch, and are released as their yolk sac is exhausted.

However it is not known whether they do form long-lived pairs bonds or if these are quite changeable (as has recently been confirmed for some seahorse species, which were also assumed to be monogamous).

In A. tentacula, the only species about which much is known, these new-born fish become free-swimming pelagic members of the plankton until they are part-grown, when they settle into their preferred adult habitat.