Most soft corals, azooxanthellae gorgonians and corals can be kept though are more delicate than soft corals and some lps's. Star, button polyps and mushrooms are also very hardy as mentioned above. Fungia(plate) corals are very pretty and different as well in my opinion.
As for the Tridacna's-I wouldn't attempt it. Especially with a nano/pico tank, they will most likely be short lived. The main reason for this is due to their inability to react and adjust to changes in anything really, from light to salinity to ph. They will stress pretty easily and to keep one in a large tank takes some close monitoring and ideal water parameters with the exception of nitrates. Clams will not survive without nitrates in your water. Granted you don't want to have high levels, but they require nitrates for food(filter feeders) as well as nano/phytoplankton and yeast as a baby-juvenile stages-then transitioning over to intense light once their zooxanthellae increases in its syphon mantle. The bacteria in their mantle(responsible for the vibrant colors, not the zooxanthellae as many might think) will prosper with plankton additions from time to time as well as nitrates adsorbed from your water column.
Hope this helps! _________ 125gal.w/Mag9.5 return(dual megaflow)>Mag7 pump Aqua Cev180skimmer.Wave2k Hamilton Reefstar(2)250watthqi(mh)pend.a Yellow, Naso Tang Red Lip Blenny Percula Clown Demoiselles Niger Trigger F. Wrasses Cerianthid Stars Hermits snails Zoos shrooms Montipora Brains Gorgonians Favia Turbinaria Kenyon Tree Acropora Xenia Tridacna (CroceaMaximaSquamosa)
"IF THE PHONE DOESN'T RING...IT'S ME"  jb
associated content.com
aka parrothead | 
