[framerguy]

As far as the size issue goes, the scarlets reach about 1.5" and red legs reach about 2.5". Their dispositions seem similar and most people seem to agree that the scarlets are the most reefsafe, however, scarlets, red, and blues are all opportunistic feeders and if they can catch something they'll eat it (which is true of most crabs that I can think of) including attacking snails and taking their shells. They will also steal food from corals (ie: shrimp from an elegance, which got all of mine bannished to the refugium), so my fuge is full of these and other criminals who have displeased me by being poopheads. My cleaner shrimps still steal food from the elegance and the trachy but I actually like them. Other criminals include two large serpent stars that got an appetite for sleeping fish, and several bumble bee snails that got an appetite for nassarius snails.