WELCOME!!
Glad to see you joined us. As for your stock list I think you will find you are severly overstocked or you tank is way undersized, however you want to look at it.
The challenge is some of the fish you list require at least a 150g-300g tank.
IMO, some of these fish should not even be in the mainstream aquarium trade because the average hobyist is unaware.
Here is a related thread:
http://www.aquariumadvice.com/viewto...001&pc_t=76105
Not sure how long you have had all these fish together or what you current water parameters are. I would highly suggest you trade/return all but the clowns if upgrading to a much larger tank is not an immediate option.
Sorry to be the bearer of bad news.
Here is a good link to get some basic info of fish before you decide on any future tankmates:
http://www.liveaquaria.com/product/categ.cfm?pcatid=15
Otherwise for suggestions for a 40g your clowns are great and you could also consider 1-2 more suitable tank mates.
Suggest you update your "my info" profile to include information about your setup such as equipment, filtration, lighting etc so we can better assist in the future.
HTH,