Filtration is also not a problem when you maintain stomatopods. Although I discourage this, I have heard of people who simply stick mantises they have caught in their reef tanks into containers without filters, and the critters do fine given enough food and partial water changes every once in a while. I myself use either traditional undergravel or power filters (which provide biological, physical, and some chemical filtration), and I'm sure the mantis loves me for this. You may also elect to skip the filter and do water changes biweekly after every feeding, since the mantis shrimps seem to be relatively picky eaters when they find out you've become their literal slave and are a regular source of food.
Mantis shrimps will generally switch to "dead" food relatively easily, once they've figured out it's either that or face a radical crash diet (I absolutely refuse to feed them live food every day). I feed them bits of shrimp (thawed from the freezer and bought at the local Pathmark store), as well as bits of mussel, squid tentacles, and crushed snail bits. I noticed that the enthusiasm for frozen foods varies between species, and maybe even among individuals. Most individuals will gladly take their daily rations from my "chopsticks" and munch enthusiastically with their upper bodies and heads sticking out of their cavities, while a few will throw out the things repeatedly. In this case, if you keep bothering them with it (i.e. keep sticking the food into their burrows/cavities) they usually relent and finally take a few bites out of the food. You may also elect to feed them less frequently (twice a week or so), in which case there will probably be less leftovers. I have not had the chance to feed them live food, although others have fed their large Odontodactylus specimens one goldfish and the like every day. I once introduced FW crayfish into the tank of a well-fed Gonodactylus individual, but all the mantis did was easily bounce the large crayfishes off the walls everytime the things wanted to go into the mantis shrimp cavity (one unlucky crayfish run well into the cavity of the mantis shrimp, prodded by the cruel author of this piece, and was promptly stunned then killed by the mantis, which then threw the body out of the cavity).
One thing that you must absolutely provide for the mantis shrimp, which is generally a cavity dwelling smasher, is some type of artificial burrow or cavity. Although some people may hesitate to do this, fearing that their "investment" might simply lay in there and not show off its luscious bod, mantis shrimps are retiring creatures that need to feel secure within the confines of an enclosed space. If you do not provide them with any shelter, they will most likely "crouch" by one wall of the container, their flanks pressed tightly against the cold and unyielding surface (hmmm, sounds like I've read too many romance novels*), and slowly and surely waste away. I generally provide my specimens with a long plastic tube (with an entry diameter 1.5-3x the diameter of the mantis shrimps), which I completely bury under pebbles or sand (in order to keep the inside of the tube dark), with only one or two entryways uncovered. The smaller mantis shrimps also seem to be satisfied making their homes inside abandoned snail and hermit crab shells, which in addition provide extremely attractive decorations inside the tank.
Lighting? Vas is das lighting? Instead of using expensive,metal halide or high-intensity fluorescent bulbs, I generally stick to regular fluorescent or even incandescent bulbs. In the case of the latter, it would be wise to make sure the temperature in small containers does not get unduly heated by the lighting. In every case, I use a 12 hour light, 12 hour dark cycle, usually through the use of preset timers. All the mantis shrimps, at one time or the other, will regularly close off the entranceways to their cavities at night, using pebbles or any other handy, and manageable object lying around. They will also do this for one or two days straight if molting.
contd