Your reef tank may be immaculate except for a rusty-brown dusting of diatomic algae on your substrate. Tired of siphoning just to have the diatoms come right back? Relatively inexpensive and highly efficient, a sand-sifting sea cucumber may be the solution you’re seeking.
There are many species of sea cucumber available in the aquarium hobby. They get their name from their elongated, cylindrical body shape. Some are colorful, some are not, some are smooth, while others appear knobby or textured. Some are filter feeders that cling to the glass, waiting for food to come to them in the water flow. There are three specific types of sand sifters that are commonly offered which do a really great job cleaning up your sand. All of them belong to the genus Holothuria and they are very efficient at what they do.
The Pink Sand-sifting Cucumber (Holothuria edulis) is found throughout the Indo-Pacific region as well as Hawaii. It can attain a size of just over 12 inches in length and boasts a striking hot pink and black coloration. These cucumbers behave like most other sand sifting cucumbers – they will lay out on the sand bed (especially at night) and extend their feeding tentacles out onto the sand. They slowly pull sand particles into their mouth, passing the substrate through their body, and cleaning the sand of any food particles, The excrete the clean sand from their other end. These bizarre and fascinating creatures actually seem to produce waste products that are cleaner than what they ingest.
The Tigertail Cucumber (Holothuria hilla) is a more attractive member of the Holothuridiidae family. These cucumbers are tan or brown with pale yellow or white “spikes”. Tigertails are amazing sand cleaners and have been hobbyist favorites for years. They are a smaller species of cucumber, often staying under 10 inches. Adding one of these cucumbers to your home aquarium will definitely start conversations as to what exactly that weird thing is and what it’s doing.
There are several species of cucumber available from Florida and the Caribbean. The White Sand-sifting Cucumber (Holothuria floridiana) is one species, but there are many that are very similar in color, pattern, texture and size, simply referred to as Caribbean common sea cucumbers in most cases. Each of these are very effective and very diligent workers when it comes to cleaning your sand bed.
So why use cucumbers? I mean, they can be toxic. As with all cucumbers, these species and others carry a slight toxin that when stressed or damaged can be released into the water column. Though beautiful, the Sea Apple has a reputation for wiping out entire aquariums! Fortunately, a good protein skimmer, fresh carbon, and a water change will mitigate the damage that could be caused by the toxins most cucumbers have. Why not use gobies, you ask? Well, sea cucumbers are probably the most efficient of the sand cleaners. The gobies tirelessly “clean” your sand in search of microfauna, like copepods. Though they stir the sand in patches, they don’t feed on the algae. Check out these cucumbers next time you need a sand cleaning solution! You won’t be disappointed in their performance.
Until next blog
Craig
Holothuria Feeding Tentacles image referenced from wikipedia and originally posted by Drow_male