Please Answer My Burning Fish Tank Questions?

[HawaiiFishCave]

1. My Fish Tank Is 48 x 15 x 13 roughly , so how many gallons would this be? , Also What Heater Would I Need? 200w?

2.Can My Tank (Tropical) Still Cycle When I Dont Have A Heater? And What do i do to start this cycle off? , i already put 1 filter pad from my other tank into the new filter? is this good?

3. how long do i have to wait till i start to add fish? - at the monent i have cold water - gravel - and a filter with one filter pad from the other tropical tank - soon i will get a heater. do i need to add aything else?

4. How Do These Syphon Graval Cleaners Work?
They Look Complcated :S -.

Thank You ;]