Welcome to the board! I think that you will find a lot of information here and if you take some of the advice you will have a splendid tank. But first off, we need to get some things straight.
Has your tank cycled yet?
How long has it been set up?
Did you add your fish all at once? How long ago?
I hope that the answers are yes, a number greater than 3 in terms of months, and no. Otherwise, you have a watery grave on your hands. Seriously, do some research and you will find that your tank, regardless of the answers to these questions, is severly overstocked and will lead to disaster.
For starters, many people would not put any tang in a tank smaller than 55 gallons let alone 46 gallons.
Secondly, Copperbanded butterfly fish have poor rates of survival in captivity, they are very picky eaters and are usually difficult to keep well fed.
The clown may be OK, but not if your tank hasnt cycled.
The best piece of advice that i can offer is to slow down. I am not trying to flame you or be mean. I do think though that you are headed for problems with your current set up and I as well as many others do not want to see the needless suffering of marine fish. What you should do is try and take some, if not all of the fish back your LFS and start over at a slower pace. a lot of times, stores will give you credit so that you dont lose any money, this way you may not have to buy your fish twice.
