Welcome
If you have not read the 3 steps, they are very helpful; they are listed under steps at the top of the page.
As for the sand bed you cane go here for a calculator for the sand bed (depending on how deep you want it)
http://www.garf.org/ and look under Calculators.
Sumps are a good thing, I do not know that much about them yet (that is an upcoming thing)
Most here recommend about 1 to 1.5 Lbs. of live rock (LR).
I have been running my tank at 76 deg with no problems.
Red slim is one of the things you will have, you may need to add some power heads to increase the water flow around the tank.
I use the Seaclone 100 skimmer, but I have heard that the Red Sea is a good one, you will have a brake in period before it will settle in a work right, then keep adjusting it to find a spot that it will work for you.
There will be other who will have more info for you, enjoy and again welcome to the Forum.
