Whats the minimum requirements for lighting?

[Cam]

If i want coral growth in my 20 gallon tank how much wattage should i be looking for do i need in the 10000k range? also if i do go to a 45 gallon what would i need then for wattage and should i go to a MH?
Thanks
Cam

[Scuba Steve]

what are the demensions of the two tanks?

[Cam]

The new 45 gallon is 24 by 24 by 18
Thanks
Cam

[SeaHorse_Fanatic]

A 150w HQI DE pendant or a 175w SE pendant would be my first choices.

[Cam]

I guess i didn't know the rules sorry for posting tank inquires in the general lounge.
Thanks for the heads up
Cheers
Cam