I'm not going to go off on you jamie, because you are overstocked, but you do know that neons are schooling fish and like to be kept with at least 6 others all the time, right? If I were you... I'd sell them/take them back to the fish store.
IMO you are not horribly overstocked, you are just plain overstocked, and it's most likely balanced out by the fact you have live plants. in fact, i'm more worried about the fact that you have a crab, and that chances are it's either a fiddler crab or a red clawed crab. both of these crabs NEED brackish water, and NEED land. they will live in a FW aquarium for a few motnhs, but will eventually perish in freshwater without access to land and without the addition of sea slat to make it brackish.I have a 5g hex on my desk at work. The residents are: 1 dwarf gourami, 2 neons, 1 bronze cory, 2 ghost shrimp, 1 little crab, 1 mystery snail, and 1 dwarf frog. Plants are: 1 java fern, 1 water sprite, and 1 broad-leaf plant that I can't remember the name of.
I have lost count of how many folks say that is HORRIBLY overstocked, and my fish couldn't POSSIBLY be happy.
The fish have been thriving for several months now, water params stay GREAT, plants are beautiful and GROWING.
I do weeky 50% water changes.
What really makes a difference is how closely you monitor your water params, and how often you do pwc.
Good luck!
No flaming.