usually its cos there scared from traveling or there getting used to there new tank.
The reason why the goldfish is at the bottom of a fish bowl is because it is dead. (edit) It may also be resting. Fish do this from time to time. If it doesn't swim about at all, then it's probably dead though.
Depends on what kind of fish they are, but it sounds like they are not getting enough oxygen, and/or the water temp might be too low.
Because there getting used to there new surroundings
I suggest that you learn more about your fish in your aquarium. One of your fish might be a bottom sucker which means that they eat all of the dirt on the side or bottom of your tank. If one of your fish are bottom suckers, that's probably the reason why your aquarium is clean. If none of your fish are bottom suckers, than somebody must be secretly cleaning your tank for you.
That is almost all fish, but maybe you are thinking of a sun fish (mola mola) in particular.
Rocket Reef but go all the way to tobors diner and then go to the bottom and fish.
Look at the fish's bottom side. If the "anal fin" is fan shaped the fish is a female, if the fin is thin and pointed like a nozzle then the fish is a male. In the male this fin is called a 'gonopodium'
The bottom dwellers on the ocean floors eat plankton and other smaller animals. The bottom of the ocean is a sustainable condition for plankton because they cannot move against a current and this leads them to be within reach of fish that feed on them.
all the way to the bottom
Dead fish. They are bottom feeders, after all.
It is not a bad thing that all of your other fish aren't on the top of the tank. It is possiable that all your other fish just like being near the bottom. For some fish it gives them a more secure feeling being near the gravel at the bottom. If your fish look unhealthy and you think there is a problem you need to ask a different question describing the symptoms.
No, just like all fish, ice fish is a cold blooded animal. They are found dwelling in the bottom portion of the Southern Ocean.