Originally posted by Shadow678
My suggestion for an excellent sand cleaner would be a sand-sifting goby, such as a a Golden-Headed Sleeper goby. They are interesting to watch, and they do an excellent job keeping your sand clean and just slightly stirred. While vaccuuming your sand will remove all the beneficial organisms, having a goby or other type of sand-sifter will benefit your sand by helping to aeriate the top layer, which keeps your sand in good condition. There are many different and interesting animals that you can add that will accomplish this task. Sand-sifting starfish are also a good choice, if you don't have any animals that will eat stars.
Only add either of these if you want a dead sand bed these critters eat all the SB infuna. Here Is a quote from Rob Toonen on Sand sifting stars.
origanly posted By Biogeek
Well, I was going to link you to a discussion of sand-sifting stars that I have posted previously, but I can't find it, so I'll have to just send it again.
First, let me start off with some background information. The "sand-sifting stars" that we see in the petshops are all Paxillosid and Valvatid sea stars, almost all in the genus Astropecten or the genus Luidia. They are similar to other sea stars in that they have a water-vascular system that functions as a hydralic method to move their bodies around. They have the typical tube-feet sticking out of the bottom of the star, which they can retract when threatened, or move independently for locomotion or burrowing. Unlike most other sea stars, however, the end of each tube foot in the majority of the "true" sand-sifting sea stars is pointed (rather than ending in the terminal sucker typical of most sea stars) for better anchorage in the sand (although there are certainly a few sand-sifting stars in these genera that retain the suckered tube feet, but they are frequently generalists that move with equal comfort on rock and sand). The Paxillosid stars have a unique type of skeletal element (bone-like ossicles called paxillae) that are umbrella-shaped, and have a bunch of mobile spines (almost like a miniature urchin if you were to look at them under a microscope) across the top. These tiny spines allow the star to clean sand off of itself when above the surface, and the umbrella-shaped ossicles are usually dense enough to cover the entire upper surface of the sea star, so that they are still able to extend the gill-like filaments (papulae are the sea star equivalent of gills in fish) to allow the animal to breath when buried in the sand (there is a nice cartoon of how this works found here). They also usually have a distinctive row of marginal spines around the edge of the star that are used for prey capture in some species, and presumably function for defense as well. Most species in these genera are very fast for a sea star, and when stimulated some species can crawl at speeds as high as 75 cm/sec (that's the Cheetah of echinoderms)! Both Astropecten and Luidia are found almost exclusively in soft, sandy bottom habitats where they burrow through the sand for protection and in search of prey (hence the name sand-sifting sea stars). I can't tell you which one you're likely to have without at least a picture of yur star, but the most common ones in the petshops tends to be Astropecten species.
If you were trying to add one of these stars into a FOWLR tank without live sand, then you probably would not be overly concerned with their predatory habits, and in fact they would probably a good addition to such tanks. However, you're asking about keeping one of these predatory stars to a reef tank with a DSB (presumably seeded with at least some live sand). Adding one to a tank in which you intend to have a deep sandbed is not such a great idea - I explained the reasons in detail in my FAMA series on sandbeds a couple of years ago, and Ron Shimek has a nice article on deep sand beds and the reasons to avoid these sea stars online here, if you're looking for more information about adding one to a tank with a deep sand bed.
These stars are almost all voracious predators that consume a wide variety of both vertebrate and invertebrate prey. They are most active at dusk and dawn, when the light regime is subdued, but their foraging behavior is likely to be somewhat disrupted by the fact that few aquarium lighting systems have a dusk and/or dawn setting (most of us just turn the lights on or off). Several studies have shown that they prefer to feed at night to during the day unless they are really hungry, and I suspect the reason that most people don't see any problem with these animals in reef tanks and deep sand beds is that they eat things while we're asleep and not really watching the tank. The stars appear to have chemosensory abilities that allow them to discriminate among prey, and there have been a couple of studies showing that they will adjust their feeding behavior and preferentially eat certain prey in response to changes in prey density. Some species actually ingest their prey, while others simply use their spiked arms to trap the prey below the sand surface, and secrete digestive enzymes to digest the captured critters into an easily swallowed paste. There is some individual variation in both prey preference and amount of time spent out during daylight hours, but the majority of these animals should prefer a shady spot to hide during the day if they are not on the hunt.
You may be able to feed it well enough that it does not make a serious dent in your sandbed population, but I asked Ron Shimek about this as well, and neither he nor I have ever seen anyone who has a really well-developed sandbed fauna (and between the two of us doing "Sandbed Safari" workshops over the years, we've seen a lot of people's sandbeds ) with these stars in their tank. If you're determined to try to keep the star anyway, keep in mind that all the members of this family of sea stars are pretty greedy feeders. In fact, gut-content analyses of 100 sea stars caught in the wild revealed that there were 91 different species of invertebrate prey eaten recently by these stars! The most common prey items they ate in the wild were snails and bivalve (clams & mussels) molluscs, but they also ate a large number of other echinoderms (including small sand dollars, sea stars, urchins, brittle stars, and sea cucumbers), polychaete worms, small crustaceans (including shrimp, crabs, and all the various 'pods), dead or foolishly slow fish, and some small cnidarians (sea pens, sea pansies and anemones that dwell in sandy areas). They can eat an incredible amount of food for a small star, and individual stars have been found with as many as 70 brittle stars in their stomach at one time! So, unless you have been providing your star with a reasonable amount of food on a regular basis, I would say that it has probably done some pretty serious grazing on your sandbed animals ever since you added it to the tank. If you have access to clams, mussels or the like cheaply from a local bait shop or such, the stars should be quite happy with that, but IME they also devour Formula One, Prime Reef, or other frozen foods of that kind quite greedily. You can feed them intentionally by sticking them into a floating breeding trap with some food if necessary, but I have found that simply placing food close to where they are crawling when the lights are out usually means that they will get the food instead of feeding the fish in the tank...
Hope that helps?
