Sand-Sifting Sea Cucumber

Holothuria floridana

Also known as Florida Sea Cucumber, Atlantic Sea Cucumber, Sand Sifting Cucumber

SaltwaterInvertebrate

Care at a glance

Temperature: 75–81°F (24–27°C)
pH: 8.1–8.4
Adult size: 7.1 in (18 cm)
Minimum tank: 20 gal (75 L)
Temperament: Peaceful
Social behavior: Solitary
Swim level: Bottom
Difficulty: Easy
Breeding: No record
Rarity: Common
Reef safe: Reef safe
Origin: Western Atlantic, including Florida, the Caribbean and the Gulf of Mexico
Family: Holothuriidae

Overview

This is a slow, peaceful sand cleaner that spends its time processing the sand bed, which helps keep it aerated and free of built-up waste. It is reef safe, since it does not touch coral, fish, or other invertebrates, and its only real impact on tankmates is competing for the same detritus a cleanup crew relies on, so stock it in an established tank rather than alongside a large existing crew of sand-sifting snails and gobies. Feed sinking pellets if the sand bed runs low on natural food, and watch for a shrinking or deflated body, an early sign it is not getting enough to eat. Acclimate it with a slow drip over an hour or more, since sea cucumbers are especially sensitive to sudden changes in salinity, and like the rest of its family it can release toxins if it is crushed, badly injured, or dies, so handle it gently and only with clean, wet hands.

In the wild

Sand-sifting sea cucumbers live throughout the western Atlantic, including Florida, the wider Caribbean, and the Gulf of Mexico, working through the sand of seagrass beds and shallow reef flats a few metres down. Much of the body often stays tucked into a rock crevice or buried while the front end works the surrounding sand. In the aquarium it needs a mature system with a real, several-centimetre sand bed and an established population of detritus and microfauna to eat, since a brand new tank simply does not have enough food in the substrate to support it.

Good to know

Holothuria floridana is a deposit-feeding sea cucumber in the family Holothuriidae, taking in mouthfuls of sand with its oral tentacles and digesting the organic film, diatoms, and microorganisms coating each grain before passing the cleaned sand back out. Adults grow to roughly 15 to 18 cm, with a soft, leathery, mottled brown to tan body. Like other holothurians it can release toxic compounds called holothurins when badly stressed or injured, though it is generally considered milder in this regard than showier filter-feeding cucumbers such as the sea apple.

Did you know

It feeds by essentially eating its way through the sand bed, stripping off the thin film of algae and microorganisms coating each grain and leaving the sand itself behind, which is what makes it such an effective natural sand cleaner.