She doesn't use tap water, she gets her water from a good saltwater fish store.
The light is has adjustable legs on it that support it about 2 inches above the top of the tank. The light strip is 20 inches long. I'm sure it's a 10 gallon tank, but she told me the light can also be used on a standard 29 gallon, since the legs are adjustable. Here's a link, I'm 99% sure this is the light she has.
http://www.hellolights.com/201xcoaqpcho.html
I also confirmed with her that her substrate is not crushed coral, it's sand. Sorry about that.
She does not know what kind of coral it is, but it looks like a variety of finger coral, with brownish orange coloration. Do you think halving the amount of light would be a problem for it?
Thanks again!