How much sand

[jumbaaa]

How much sand
and crushed coral should i put in a 55 gallon tank? whats the ideal depth.
I have a little under 100 lbs of live rock for it.

 

[jjamontan]

I have 90lb of sand in my tank, I have heard that for a deep sand bed it needs to be 4-5". Crushed coral trap bad things in it.