Black Sea Cucumber (Holothuria Atra)

Species Name : Holothuria Atra

Care Level : Expert Only

Temperament : Peaceful

Color : Black

Diet : Filter Feeder, Omnivore

Reef Compatible : Yes

Water Conditions : 72-78° F, dKH 8-12, pH 8.1-8.4, sg 1.023-1.025

Max. Size : 8"

Family : Holothuriidae

Waterflow : Medium

Origin : Indo-Pacific 

Supplements : Iodine, Trace Elements

Holothuria Atra, commonly known as the Black Sea Cucumber or Lollyfish, is a species of marine invertebrate in the family Holothuriidae. 

Holothuria Atra is a sea cucumber that can grow to a length of 60 centimetres (24 in) but 20 centimetres (7.9 in) is a more common size. It has a smooth, pliable, entirely black skin which often has sand adhering to it, especially in smaller individuals. The mouth is on the underside at one end and is surrounded by a fringe of 20, black, branched tentacles. The anus is at the other end. 

As a defence against predators, Holothuria Atra emits a toxic red fluid when its skin is rubbed or damaged. When attacked, it does not eject Cuvierian tubules in the way that some sea cucumbers do, but instead extrudes its internal organs through its anus.

It lives in the sandy bottom, often partially covered with sand. Do not overstock an aquarium with the Black Sea Cucumber. In general, keep only 3 inches of worm for every 20 gallons of water. Also make sure to protect cucumber from being sucked into an overflow box or pump intake. 

The Black Sea Cucumber needs to be kept with peaceful tank mates. Do not keep with aggressive fishes that are not safe with invertebrates. 

It is very sensitive to high levels of copper-based medications and will not tolerate high nitrate levels.

They reproduce by means of asexual fission where they will break into two cucumbers.

Holothuria Atra is an omnivore, sifting through the sediment with its tentacles and feeding on detritus and other organic matter. 

Size: Small: 1" to 3"; Medium: 3: to 5"; Large: 5" to 7"