shrimp or lobster for community tank?

there are a lot of shrimp species that are good for community tanks. i've personally only ever kept ghost shrimp, but they usually get eaten in my tanks. but seeing as i get them 10/$1, i can live with that. they're neat little guys. i'm sure someone on here can tell you more about other shrimp species, like amano shrimp for example. however, i've never seen these in any lfs.

as far as "lobsters"...well, crayfish being the freshwater equivalent. they do NOT do well in community tanks, and i would STRONGLY advise against trying these, lest you risk losing all your fish to their incredibly overzealous appetite.

Shrimps do well in community tnaks where there is no fish big enough to eat them. Buti'm afraid in your setup it won't work as the clowns would likely eat them.

Crayfish don't do too well with other fish. They will eat your fish. A friend of mine said his crayfish ate his 6" frontosa. Best kept as a species tank

You might consider a Bamboo Shrimp (aka Wood Shimp). They're pretty big (around 2 or 3 in.), so unless your clowns are monsters the shrimp should be safe with a few hiding places. There's not a lot of info on the net about them, but I found this:

http://userpages.umbc.edu/~rrhudy1/shrimp2.htm#wood

I don't like using wood shrimp in mixed tanks and never do anymore, it is too hard to feed them with the competition.

bamboo shrimp are soooo easy to keep, and really cool critters, competition doesnt matter, they are filter feeders and can live off what *looks* like nothing. i've had my guy (he's a big one alittle over the 3" mark) in a 20 gal community, a 55 gal tanganyikan (3 peacocks), and a 38 gallon mbuna (and a ishmeali hap) i have never at all paid attention to feeding him, and he has grown and has amaizing colors. i highly recommend bamboo shrimp, they help keep your water clear, and are near 0 bioload.

you dont AT ALL have to worry about feeding them. and the thing about a hiding place wont work too well since they need a place with some current (no you dont have to add a powerhead or anything) so a cave or something wont be very ideal. he might use it when you first introduce him, and once in a while. most of the time he will be roosting on top of something with his fans open (often the filter intake tube.

Un huh, and you really think that a 3" heavy-bodied critter is zero bioload?

Yeah, sure.

their anatomy enables them to live off very near nothing, resulting in much less waste production. i believe crustacians produce less waste than fish anyways, being a filter feeder just makes it even less.