Ask your favorite Wrasse about it’s sleeping tips!

Humans have many methods and tricks they can employ to help them sleep, but for a saltwater wrasse it’s dependent on its particular sleeping behavior. It may surprise you to know that not all wrasses bury themselves in the sand at night! When keeping saltwater wrasses, either a high-rise condo or a sand flat could be the place of choice.

Each of the various wrasse species beds down at night in a particular area of the tank, either the sub-level or the upper-level. In fact, there are an equal amount of wrasses that sleep in the sand and sleep in the rockwork. Out of the rockwork sleepers, a few genuses will even spin a mucus cocoon to mask their scent from predators!

Knowing the habitat requirements of an individual species can be confusing though, as retailers themselves aren’t always sure or may just assume they all bury themselves. The best way to prepare a proper home for your new wrasse is to know which genus’ bury themselves in the sand and which genus’ just sleep in caves and crevices among the rockwork.

Facts about wrasse sleeping behaviors and protective strategies

Sand-sleeping Wrasses

Wrasses that bury themselves at night are undisturbed by most nocturnal predators. Yet there are some predators that use sonar to locate creatures under the sand, and those pose the greatest risk to buriers. But even if detected, most of the time the wrasse has a chance to shoot out of the sand in an attempt to escape. Still there may be another predator swimming by just looking to take advantage of an unearthed morsel!

During the day, these wrasses will also take refuge in the sand if they feel threatened. Juveniles may also stay in the sand during growth changes. My Halichoeres garnoti, right before a growth spurt and color change, will stay in the sand for most of the day. So don’t get too worried and go looking for your juvenile buriers, they are just getting some extra sleep!


Cocoon Spinning Wrasses

The wrasses that spin mucus cocoons have an interesting strategy. They not only sleep in their cocoon, but it masks their scent from predators. Being in a cocoon still allows these wrasses to be alert to any predators that may find them accidentally, and it allows them a chance to escape quickly. This is an advantage over many other reef fish that are just hiding in the rock, as they are subject to getting flushed out and ambushed by night predators.


Cave and Crevice Sleeping Wrasses

The last group consists of the wrasses that, like other fish in the reef, will just hide in caves at night. Certain genus’ that sleep in the rockwork without a mucus cocoon will still hide in the sand if frightened, but they do not sleep in the sand.

Spectacled wrasse lying on the reef
Image Credit: yuuno0606, Shutterstock

What about the substrate?

What to use for a substrate is really one of the very first decisions you will make as a new saltwater aquarist. You’ll need to decide if you should you use a sand or crushed coral, both, or none. Thinking of your future inhabitants and their needs will help you make the best decision.

If you are going to have a wrasse that buries itself, whether out of fear or at night, sand is really your only choice. Personally, I feel about 2″ to 3″ of sand is by far the most superior substrate, and a sand designed for marine tanks can help keep the pH high. Though people like crushed coral for various reasons, it can lacerate your pet, causing sores, infection, and possibly death if not treated immediately. Crushed coral also tends to compact and needs to be mechanically stirred to keep debris from getting stuck and then rotting.

Bare bottom or Berlin tanks will work fine for wrasses that spin cocoons at night to sleep in, or who just sleep in the rockwork like other fish. But this type of tank is not the best choice for the wrasses who bury themselves at night or when frightened. These wrasses need that security or they will stress and eventually become sick, because that is what stressed fish do! One option is to add a sand filled plastic bowel that is longer than your wrasse but is at least 3″ deep. Believe me, your wrasse will find that bowl! This is also a great idea in a quarantine tank.

Black Leopard wrasse
Image Credit: Vojce, Shutterstock

Sleeping behaviors for various wrasse species

This quick reference guide will help you decide which genus you want, and what substrate is the best. Below are wrasses grouped by sleeping habits. Some wrasses go sub-level at night and some stay in the upper levels within the rock.

They are listed by the common names given for a group or an individual species, followed by the genus name. Those with an asterisk * by their genus name do not sleep in the sand at night, but will still hide in the sand during the day if startled. These fish are also very active and have to rest during the day, so don’t get worried if they are resting on the sand or in the rockwork.

Sand Sleepers:

  • Candycane Wrasses / Ring Wrasses: (Genus Hologymnosus)
  • Chiseltooth Wrasse: (Genus Pseudodax)
  • Coris Wrasses: (Genus Coris)
  • DragonWrasse: (Genus Novaculichthys)
  • Halichoeres Wrasses: (Genus Halichoeres)
  • Leopard Wrasses: (Genus Macropharyngodon)
  • Pencil Wrasses: (Genus Pseudojuloides)
  • Tamarin Wrasses: Genus Anampses
  • Razorfish group 1: (Genus Cymolutes)
  • Razorfish group 2: (Genus Hemipteronotus)
  • Razorfish group 3: (Genus Iniistius)
  • Razorfish group 4: (Genus Xyrichtys)
  • Rockmover Wrasses: (Genus Novaculichthys)

Cocoon Mucus Spinners:

  • Fairy Wrasses: (Genus Cirrhilabrus)
  • Flasher Wrasses: (Genus Paracheilinus)
  • Lined Wrasses: (Genus Pseudocheilinus)

Cave and Crevice Sleepers:

  • Banana Wrasse: (Genus Thalassoma)*
  • Bird Wrasses: (Genus Gomphosus)*
  • Cleaner Wrasses: (Genus Labroides)
  • Hogfish: (Genus Bodianus)*
  • Maori Wrasses: (Genus Oxychilinus)
  • Possum Wrasses: (Genus Wetmorella)
  • Ribbon Wrasse: (Genus Stethojulis)
  • Secretive Wrasse: (genus Pteragogus)
  • Tuskfish: (Genus Choerodon)
  • Thicklip Wrasses: (Genus Hemigymnus)*

So keep this handy as a quick reference. Wrasses have amazing personalities, with each genus being different from the others. Their constant movement makes them very enjoyable to watch!

Carrie McBirney is a team member at Animal-World and has contributed many articles and write-ups.


Featured Image Credit: Laura Dts, Shutterstock