While searching for the sand synaptids, as shown below, I often come across a sea cucumber species sharing exactly the same habitat as the synaptids, always found at least six inches deep in the sandbed areas located at the edges of sea grass beds. At first, I thought that much like other sea cucumbers that they were just using the sand as a day time hiding place, but noting that they are only ever found by me seeming to share the same habits as the synaptids, I took one home and placed it within my aquariums deep sand bed. For a period of three months, I never once saw it come up out of the sandbed yet often saw it up against the glass of the aquarium always at least three inches down. Noting a few extra sand "volcanoes" than normal each morning was another clue as to what this sea cucumber was doing. I fully believe that this species of sea cucumber never comes up out of the sand and spends its life injesting sand grains for organic material much like a surface dwelling sea cucumber does.
  Considering the hobbyists who do not have the luxory of collecting tropical live sand for their DSB and can only hope that the live sand they purchase contains the needed sand infauna to make a deep live sand bed functional, I believe that both this and the synaptid species, if ever introduced or exported to the hobby, would negate a great many concerns with live deep sand beds and at the same time, eliminate the constant need to replenish the tiny sand infauna that we rely upon now, which can be almost impossible to replenish without having to purchase even more live sand to exchange within the aquarium.

   While not actualy a worm, this family group of sea cucumbers get their nick name simply due to their long, skinny appearance and their lack of any obvious legs, that, and having a crown of feeding appendages that stand out. I see a great many Synaptids out on the sea grass beds crawling along ever so slowly while they mop up the abundant organic debris. With no visible means of propulsion (legs), I had often wondered at how they move themselves across the substrates. It was my wife Linda who quite by accident discovered how they do so. Having microscopic "hooks" covering their skin, enables them to be very "sticky", which Linda found out when her bare leg brushed against one while snorkeling and had it stick to her. Needless to say, She did a fairly good imitation of Jesus as she walked on water back to shore while screaming like a girl.  Being that "sticky" allows the synaptids to anchor any one section of themselves and move across the substrates in an inch worm fashion.

   THE APODIDA :  Contains about 269 species in 32 genera and three families. Tentacles are digitate, pinnate or, in some small species, simple. Respiratory trees are absent. Tube feet are completely absent. The calcareous ring is without posterior projections. The body wall is very thin and often transparent. Found in both shallow and deep water.

   Sand Dwelling Species :  While searching through the near shore sand beds for various worm species, I came across the species shown in the below photos. I remembered how the surface dwelling species are very efficient at collecting organic particles and thought that might the sand dwelling types be as equally efficient.
   Being that our aquarium's deep sand beds are the only truly organic loaded environment we have, and strive to maintain the sand infauna that keeps our deep sand beds functional, I thought with these synaptids, I might be able to avoid the possible problems that an organic laden sand bed might cause to my aquarium system and collected three of them for my deep sand bed. Having had them for quite a length of time now, I can say that they are indeed a great benefit to my deep sand bed. They spend their entire time moving slowly through entire depth of the sand bed injesting the sand and cleaning it of any organics. Their movement through the sand bed also ensures that there are no pockets of stagnant water and sand while at the same time, slowly shifting the sand between the upper and lower levels, preventing any formations of clumps.
   I believe this single species will eventually become popular with reef keeping hobbyists as a means to maintain deep sand beds with little to no effort while enjoying not having to repopulate the normal microscopic sand infauna, it appears that these synaptids easily take over such roles. In due time, it is my hope to introduce these synaptids to the hobby and make our keeping of marine systems a bit easier and much more natural. Might then the deep sand bed critics be forced to find a different dead horse to beat upon.

   Normaly I would not recommend the surface dwelling synaptids as a member of a reef aquarium simply because they require a great deal of organic debris to survive. Not something our aquarium systems are set up to provide. That and most species are fairly large, the most commonly seen species here in the Philippines averages two to six feet long. However, on occassion, I do get a small species that hitch hikes in with live rock and appears to do well. Keep in mind that this is an animal that is at the most, two inches long (as shown below) and is the only one in the entire aquarium system. Being that small most likely allows it to just get by on what my system can provide for in the way of organic debris. The smaller species also tend to be nocturnal and rarely seen.