well, i have ot comment on youtr title,
YOU ARE NOT AN IDIOT!!!!!
the best thing you did was recognize the fact that you weren't sure, then sought the answer, so therefore youare smarter than the average reef keeper, and you are planning ahed, i must say you are more intelligent than you give yourself credit for, by not assuming or guessing
body type, and also consider the tang(species size), in stocking limits as well, however there are no guarentees, this is only a generla rule
HTH