Hi Jenni,
First things first, we need to know your tank parameters, tank size, how long it has been running and most importantly, is it cycled?
If you can test your water and post on here, it will help us suggest and remedie any problems we can see as most issues revolve around poor water quality. Your water tests should include ammonia, nitrite and nitrate. Ammonia and nitrite should both read 0ppm. Both of these can kill fish and I suspect yours are suffering from nitrite poisoning. The nitrite basically stops the fish from absorbing oxygen, which could be a reason they are hanging around the surface. Nitrate is the final product of the nitrogen cycle (ammonia turns to nitrite which turns to the end product, nitrate) and is far less toxic than the other 2 and is eradicated by your weekly water changes.
Did you acclimatise the fish properly and leave the lights switched off?
Have a look at the beginners resource centre, especially the topics about cycling.